Programs & Examples On #Neuroscience

Alternative for <blink>

You could take advantage of JavaScript's setInterval function:

_x000D_
_x000D_
const spanEl = document.querySelector('#spanEl');_x000D_
var interval = setInterval(function() {_x000D_
  spanEl.style.visibility = spanEl.style.visibility === "hidden" ? 'visible' : 'hidden';_x000D_
}, 250);
_x000D_
<span id="spanEl">This text will blink!</span>
_x000D_
_x000D_
_x000D_

The type arguments for method cannot be inferred from the usage

As I mentioned in my comment, I think the reason why this doesn't work is because the compiler can't infer types based on generic constraints.

Below is an alternative implementation that will compile. I've revised the IAccess interface to only have the T generic type parameter.

interface ISignatur<T>
{
    Type Type { get; }
}

interface IAccess<T>
{
    ISignatur<T> Signature { get; }
    T Value { get; set; }
}

class Signatur : ISignatur<bool>
{
    public Type Type
    {
        get { return typeof(bool); }
    }
}

class ServiceGate
{
    public IAccess<T> Get<T>(ISignatur<T> sig)
    {
        throw new NotImplementedException();
    }
}

static class Test
{
    static void Main()
    {
        ServiceGate service = new ServiceGate();
        var access = service.Get(new Signatur());
    }
}

Socket.IO handling disconnect event

For those like @sha1 wondering why the OP's code doesn't work -

OP's logic for deleting player at server side is in the handler for DelPlayer event, and the code that emits this event (DelPlayer) is in inside disconnected event callback of client.

The server side code that emits this disconnected event is inside the disconnect event callback which is fired when the socket loses connection. Since the socket already lost connection, disconnected event doesn't reach the client.


Accepted solution executes the logic on disconnect event at server side, which is fired when the socket disconnects, hence works.

Sending cookies with postman

Even after toggling it did not work. I closed and restarted the browser after adding the postman plugin, logged into the site to generate cookies afresh and then it worked for me.

How do I create a file at a specific path?

The file is created wherever the root of the python interpreter was started.

Eg, you start python in /home/user/program, then the file "test.py" would be located at /home/user/program/test.py

.htaccess not working on localhost with XAMPP

for xampp vm on MacOS capitan, high sierra, MacOS Mojave (10.12+), you can follow these

1. mount /opt/lampp
2. explore the folder
3. open terminal from the folder
4. cd to `htdocs`>yourapp (ex: techaz.co)
5. vim .htaccess
6. paste your .htaccess content (that is suggested on options-permalink.php)

enter image description here

How to set border on jPanel?

An empty border is transparent. You need to specify a Line Border or some other visible border when you set the border in order to see it.

Based on Edit to question:

The painting does not honor the border. Add this line of code to your test and you will see the border:

    jboard.setBorder(BorderFactory.createEmptyBorder(0,10,10,10)); 
    jboard.add(new JButton("Test"));  //Add this line
    frame.add(jboard);

How do I declare a two dimensional array?

Firstly, PHP doesn't have multi-dimensional arrays, it has arrays of arrays.

Secondly, you can write a function that will do it:

function declare($m, $n, $value = 0) {
  return array_fill(0, $m, array_fill(0, $n, $value));
}

Laravel form html with PUT method for PUT routes

You CAN add css clases, and any type of attributes you need to blade template, try this:

{{ Form::open(array('url' => '/', 'method' => 'PUT', 'class'=>'col-md-12')) }}
.... wathever code here
{{ Form::close() }}

If you dont want to go the blade way you can add a hidden input. This is the form Laravel does, any way:

Note: Since HTML forms only support POST and GET, PUT and DELETE methods will be spoofed by automatically adding a _method hidden field to your form. (Laravel docs)

<form class="col-md-12" action="<?php echo URL::to('/');?>/post/<?=$post->postID?>" method="POST">

    <!-- Rendered blade HTML form use this hidden. Dont forget to put the form method to POST -->

    <input name="_method" type="hidden" value="PUT">

    <div class="form-group">
        <textarea type="text" class="form-control input-lg" placeholder="Text Here" name="post"><?=$post->post?></textarea>
    </div>

    <div class="form-group">
        <button class="btn btn-primary btn-lg btn-block" type="submit" value="Edit">Edit</button>
    </div>
</form>

Loop through columns and add string lengths as new columns

You can use lapply to pass each column to str_length, then cbind it to your original data.frame...

library(stringr)

out <- lapply( df , str_length )    
df <- cbind( df , out )

#     col1     col2 col1 col2
#1     abc adf qqwe    3    8
#2    abcd        d    4    1
#3       a        e    1    1
#4 abcdefg        f    7    1

What are the Ruby File.open modes and options?

In Ruby IO module documentation, I suppose.

Mode |  Meaning
-----+--------------------------------------------------------
"r"  |  Read-only, starts at beginning of file  (default mode).
-----+--------------------------------------------------------
"r+" |  Read-write, starts at beginning of file.
-----+--------------------------------------------------------
"w"  |  Write-only, truncates existing file
     |  to zero length or creates a new file for writing.
-----+--------------------------------------------------------
"w+" |  Read-write, truncates existing file to zero length
     |  or creates a new file for reading and writing.
-----+--------------------------------------------------------
"a"  |  Write-only, starts at end of file if file exists,
     |  otherwise creates a new file for writing.
-----+--------------------------------------------------------
"a+" |  Read-write, starts at end of file if file exists,
     |  otherwise creates a new file for reading and
     |  writing.
-----+--------------------------------------------------------
"b"  |  Binary file mode (may appear with
     |  any of the key letters listed above).
     |  Suppresses EOL <-> CRLF conversion on Windows. And
     |  sets external encoding to ASCII-8BIT unless explicitly
     |  specified.
-----+--------------------------------------------------------
"t"  |  Text file mode (may appear with
     |  any of the key letters listed above except "b").

Symfony2 Setting a default choice field selection

If you want to pass in an array of Doctrine entities, try something like this (Symfony 3.0+):

protected $entities;
protected $selectedEntities;

public function __construct($entities = null, $selectedEntities = null)
{
    $this->entities = $entities;
    $this->selectedEntities = $selectedEntities;
}

public function buildForm(FormBuilderInterface $builder, array $options)
{
    $builder->add('entities', 'entity', [
        'class' => 'MyBundle:MyEntity',
        'choices' => $this->entities,
        'property' => 'id',
        'multiple' => true,
        'expanded' => true,
        'data' => $this->selectedEntities,
    ]);
}

vba listbox multicolumn add

Simplified example (with counter):

With Me.lstbox
    .ColumnCount = 2
    .ColumnWidths = "60;60"
    .AddItem
    .List(i, 0) = Company_ID
    .List(i, 1) = Company_name 
    i = i + 1

end with

Make sure to start the counter with 0, not 1 to fill up a listbox.

How to fix the error "Windows SDK version 8.1" was not found?

I faced this problem too. Re-ran the Visual Studio 2017 Installer, go to 'Individual Components' and select Windows 8.1 SDK. Go back to to the project > Right click and Re-target to match the SDK required as shown below:enter image description here

Multiple controllers with AngularJS in single page app

You could also have embed all of your template views into your main html file. For Example:

<body ng-app="testApp">
  <h1>Test App</h1>
  <div ng-view></div>
  <script type = "text/ng-template" id = "index.html">
    <h1>Index Page</h1>
    <p>{{message}}</p>
  </script>
  <script type = "text/ng-template" id = "home.html">
    <h1>Home Page</h1>
    <p>{{message}}</p>
  </script>
</body>

This way if each template requires a different controller then you can still use the angular-router. See this plunk for a working example http://plnkr.co/edit/9X0fT0Q9MlXtHVVQLhgr?p=preview

This way once the application is sent from the server to your client, it is completely self contained assuming that it doesn't need to make any data requests, etc.

jQuery make global variable

You can avoid declaration of global variables by adding them directly to the global object:

(function(global) {

  ...

  global.varName = someValue;

  ...

}(this));

A disadvantage of this method is that global.varName won't exist until that specific line of code is executed, but that can be easily worked around.

You might also consider an application architecture where such globals are held in a closure common to all functions that need them, or as properties of a suitably accessible data storage object.

Best tool for inspecting PDF files?

There is also another option. Adobe Acrobat Pro is also able to display the internal tree structure of the PDF.

  1. Open Preflight
  2. Go to Options (right upper corner)
  3. Internal PDF Structure

On top Adobe Acrobat Pro can also display the internal structure of the Document Fonts in the PDF most of other "PDF tree structure viewer" don't have this otion

enter image description here

Array initialization syntax when not in a declaration

Why is this blocked by Java?

You'd have to ask the Java designers. There might be some subtle grammatical reason for the restriction. Note that some of the array creation / initialization constructs were not in Java 1.0, and (IIRC) were added in Java 1.1.

But "why" is immaterial ... the restriction is there, and you have to live with it.

I know how to work around it, but from time to time it would be simpler.

You can write this:

AClass[] array;
...
array = new AClass[]{object1, object2};

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

If you use Git and have Git Bash installed you can open a Git Bash at the directory (via Right Click in the white space in Explorer > Git Bash Here) and do:

touch .htaccess

How to read from stdin with fgets()?

Exits the loop if the line is empty(Improving code).

#include <stdio.h>
#include <string.h>

// The value BUFFERSIZE can be changed to customer's taste . Changes the
// size of the base array (string buffer )    
#define BUFFERSIZE 10

int main(void)
{
    char buffer[BUFFERSIZE];
    char cChar;
    printf("Enter a message: \n");
    while(*(fgets(buffer, BUFFERSIZE, stdin)) != '\n')
    {
        // For concatenation
        // fgets reads and adds '\n' in the string , replace '\n' by '\0' to 
        // remove the line break .
/*      if(buffer[strlen(buffer) - 1] == '\n')
            buffer[strlen(buffer) - 1] = '\0'; */
        printf("%s", buffer);
        // Corrects the error mentioned by Alain BECKER.       
        // Checks if the string buffer is full to check and prevent the 
        // next character read by fgets is '\n' .
        if(strlen(buffer) == (BUFFERSIZE - 1) && (buffer[strlen(buffer) - 1] != '\n'))
        {
            // Prevents end of the line '\n' to be read in the first 
            // character (Loop Exit) in the next loop. Reads
            // the next char in stdin buffer , if '\n' is read and removed, if
            // different is returned to stdin 
            cChar = fgetc(stdin);
            if(cChar != '\n')
                ungetc(cChar, stdin);
            // To print correctly if '\n' is removed.
            else
                printf("\n");
        }
    }
    return 0;
}

Exit when Enter is pressed.

#include <stdio.h>
#include <stdbool.h>
#include <string.h>
#include <assert.h>

#define BUFFERSIZE 16

int main(void)
{
    char buffer[BUFFERSIZE];
    printf("Enter a message: \n");
    while(true)
    {
        assert(fgets(buffer, BUFFERSIZE, stdin) != NULL);
        // Verifies that the previous character to the last character in the
        // buffer array is '\n' (The last character is '\0') if the
        // character is '\n' leaves loop.
        if(buffer[strlen(buffer) - 1] == '\n')
        {
            // fgets reads and adds '\n' in the string, replace '\n' by '\0' to 
            // remove the line break .
            buffer[strlen(buffer) - 1] = '\0';
            printf("%s", buffer);
            break;
        }
        printf("%s", buffer);   
    }
    return 0;
}

Concatenation and dinamic allocation(linked list) to a single string.

/* Autor : Tiago Portela
   Email : [email protected]
   Sobre : Compilado com TDM-GCC 5.10 64-bit e LCC-Win32 64-bit;
   Obs : Apenas tentando aprender algoritimos, sozinho, por hobby. */

#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
#include <assert.h>

#define BUFFERSIZE 8

typedef struct _Node {
    char *lpBuffer;
    struct _Node *LpProxNode;
} Node_t, *LpNode_t;

int main(void)
{
    char acBuffer[BUFFERSIZE] = {0};
    LpNode_t lpNode = (LpNode_t)malloc(sizeof(Node_t));
    assert(lpNode!=NULL);
    LpNode_t lpHeadNode = lpNode;
    char* lpBuffer = (char*)calloc(1,sizeof(char));
    assert(lpBuffer!=NULL);
    char cChar;


    printf("Enter a message: \n");
    // Exit when Enter is pressed
/*  while(true)
    {
        assert(fgets(acBuffer, BUFFERSIZE, stdin)!=NULL);
        lpNode->lpBuffer = (char*)malloc((strlen(acBuffer) + 1) * sizeof(char));
        assert(lpNode->lpBuffer!=NULL);
        strcpy(lpNode->lpBuffer, acBuffer);
        if(lpNode->lpBuffer[strlen(acBuffer) - 1] == '\n')
        {
            lpNode->lpBuffer[strlen(acBuffer) - 1] = '\0';
            lpNode->LpProxNode = NULL;
            break;
        }
        lpNode->LpProxNode = (LpNode_t)malloc(sizeof(Node_t));
        lpNode = lpNode->LpProxNode;
        assert(lpNode!=NULL);
    }*/

    // Exits the loop if the line is empty(Improving code).
    while(true)
    {
        assert(fgets(acBuffer, BUFFERSIZE, stdin)!=NULL);
        lpNode->lpBuffer = (char*)malloc((strlen(acBuffer) + 1) * sizeof(char));
        assert(lpNode->lpBuffer!=NULL);
        strcpy(lpNode->lpBuffer, acBuffer);
        if(acBuffer[strlen(acBuffer) - 1] == '\n')
            lpNode->lpBuffer[strlen(acBuffer) - 1] = '\0';
        if(strlen(acBuffer) == (BUFFERSIZE - 1) && (acBuffer[strlen(acBuffer) - 1] != '\n'))
        {
            cChar = fgetc(stdin);
            if(cChar != '\n')
                ungetc(cChar, stdin);
        }
        if(acBuffer[0] == '\n')
        {
            lpNode->LpProxNode = NULL;
            break;
        }
        lpNode->LpProxNode = (LpNode_t)malloc(sizeof(Node_t));
        lpNode = lpNode->LpProxNode;
        assert(lpNode!=NULL);
    }


    printf("\nPseudo String :\n");
    lpNode = lpHeadNode;
    while(lpNode != NULL)
    {
        printf("%s", lpNode->lpBuffer);
        lpNode = lpNode->LpProxNode;
    }


    printf("\n\nMemory blocks:\n");
    lpNode = lpHeadNode;
    while(lpNode != NULL)
    {
        printf("Block \"%7s\" size = %lu\n", lpNode->lpBuffer, (long unsigned)(strlen(lpNode->lpBuffer) + 1));
        lpNode = lpNode->LpProxNode;
    }


    printf("\nConcatenated string:\n");
    lpNode = lpHeadNode;
    while(lpNode != NULL)
    {
        lpBuffer = (char*)realloc(lpBuffer, (strlen(lpBuffer) + strlen(lpNode->lpBuffer)) + 1);
        strcat(lpBuffer, lpNode->lpBuffer);
        lpNode = lpNode->LpProxNode;
    }
    printf("%s", lpBuffer);
    printf("\n\n");

    // Deallocate memory
    lpNode = lpHeadNode;
    while(lpNode != NULL)
    {
        lpHeadNode = lpNode->LpProxNode;
        free(lpNode->lpBuffer);
        free(lpNode);
        lpNode = lpHeadNode;
    }
    lpBuffer = (char*)realloc(lpBuffer, 0);
    lpBuffer = NULL;
    if((lpNode == NULL) && (lpBuffer == NULL))
    {

        printf("Deallocate memory = %s", (char*)lpNode);
    }
    printf("\n\n");

    return 0;
}

How to get UTF-8 working in Java webapps?

Some time you can solve problem through MySQL Administrator wizard. In

Startup variables > Advanced >

and set Def. char Set:utf8

Maybe this config need restart MySQL.

Using the last-child selector

If you think you can use Javascript, then since jQuery support last-child, you can use jQuery's css method and the good thing it will support almost all the browsers

Example Code:

$(function(){
   $("#nav li:last-child").css("border-bottom","1px solid #b5b5b5")
})

You can find more info about here : http://api.jquery.com/css/#css2

ModuleNotFoundError: What does it mean __main__ is not a package?

Try to run it as:

python3 -m p_03_using_bisection_search

`&mdash;` or `&#8212;` is there any difference in HTML output?

SGML parsers (or XML parsers in the case of XHTML) can handle &#8212; without having to process the DTD (which doesn't matter to browsers as they just slurp tag soup), while &mdash; is easier for humans to read and write in the source code.

Personally, I would stick to a literal em-dash and ensure that my character encoding settings were consistent.

How to automatically indent source code?

In 2010 it is ctrl +k +d for indentation

Choosing the best concurrency list in Java

Any Java collection can be made to be Thread-safe like so:

List newList = Collections.synchronizedList(oldList);

Or to create a brand new thread-safe list:

List newList = Collections.synchronizedList(new ArrayList());

http://download.oracle.com/javase/6/docs/api/java/util/Collections.html#synchronizedList(java.util.List)

Referencing system.management.automation.dll in Visual Studio

If you don't want to install the Windows SDK you can get the dll by running the following command in powershell:

Copy ([PSObject].Assembly.Location) C:\

What is causing ImportError: No module named pkg_resources after upgrade of Python on os X?

In case of upgrading your python on mac os 10.7 and pkg_resources doesn't work, the simplest way to fix this is just reinstall setuptools as Ned mentioned above.

sudo pip install setuptools --upgrade
or sudo easy_install install setuptools --upgrade

Determine .NET Framework version for dll

You have a few options: To get it programmatically, from managed code, use Assembly.ImageRuntimeVersion:

Dim a As Assembly = Reflection.Assembly.ReflectionOnlyLoadFrom("C:\path\assembly.dll")
Dim s As String = a.ImageRuntimeVersion

From the command line, starting in v2.0, ildasm.exe will show it if you double-click on "MANIFEST" and look for "Metadata version". Determining an Image’s CLR Version

Return JSON with error status code MVC

A simple way to send a error to Json is control Http Status Code of response object and set a custom error message.

Controller

public JsonResult Create(MyObject myObject) 
{
  //AllFine
  return Json(new { IsCreated = True, Content = ViewGenerator(myObject));

  //Use input may be wrong but nothing crashed
  return Json(new { IsCreated = False, Content = ViewGenerator(myObject));  

  //Error
  Response.StatusCode = (int)HttpStatusCode.InternalServerError;
  return Json(new { IsCreated = false, ErrorMessage = 'My error message');
}

JS

$.ajax({
     type: "POST",
     dataType: "json",
     url: "MyController/Create",
     data: JSON.stringify(myObject),
     success: function (result) {
       if(result.IsCreated)
     {
    //... ALL FINE
     }
     else
     {
    //... Use input may be wrong but nothing crashed
     }
   },
    error: function (error) {
            alert("Error:" + erro.responseJSON.ErrorMessage ); //Error
        }
  });

How do I compute derivative using Numpy?

You have four options

  1. Finite Differences
  2. Automatic Derivatives
  3. Symbolic Differentiation
  4. Compute derivatives by hand.

Finite differences require no external tools but are prone to numerical error and, if you're in a multivariate situation, can take a while.

Symbolic differentiation is ideal if your problem is simple enough. Symbolic methods are getting quite robust these days. SymPy is an excellent project for this that integrates well with NumPy. Look at the autowrap or lambdify functions or check out Jensen's blogpost about a similar question.

Automatic derivatives are very cool, aren't prone to numeric errors, but do require some additional libraries (google for this, there are a few good options). This is the most robust but also the most sophisticated/difficult to set up choice. If you're fine restricting yourself to numpy syntax then Theano might be a good choice.

Here is an example using SymPy

In [1]: from sympy import *
In [2]: import numpy as np
In [3]: x = Symbol('x')
In [4]: y = x**2 + 1
In [5]: yprime = y.diff(x)
In [6]: yprime
Out[6]: 2·x

In [7]: f = lambdify(x, yprime, 'numpy')
In [8]: f(np.ones(5))
Out[8]: [ 2.  2.  2.  2.  2.]

How to make script execution wait until jquery is loaded

Rather than "wait" (which is usually done using setTimeout), you could also use the defining of the jQuery object in the window itself as a hook to execute your code that relies on it. This is achievable through a property definition, defined using Object.defineProperty.

(function(){
  var _jQuery;
  Object.defineProperty(window, 'jQuery', {
    get: function() { return _jQuery; },
    set: function($) {
      _jQuery = $;

      // put code or call to function that uses jQuery here

    }
  });
})();

Bootstrap: add margin/padding space between columns

I had the same issue and worked it out by nesting a div inside bootstrap col and adding padding to it. Something like:

<div class="container">
 <div class="row">
  <div class="col-md-4">
   <div class="custom-box">Your content with padding</div>
  </div>
  <div class="col-md-4">
   <div class="custom-box">Your content with padding</div>
  </div>
  <div class="col-md-4">
   <div class="custom-box">Your content with padding</div>
  </div>
 </div>
</div>

Can I set max_retries for requests.request?

Be careful, Martijn Pieters's answer isn't suitable for version 1.2.1+. You can't set it globally without patching the library.

You can do this instead:

import requests
from requests.adapters import HTTPAdapter

s = requests.Session()
s.mount('http://www.github.com', HTTPAdapter(max_retries=5))
s.mount('https://www.github.com', HTTPAdapter(max_retries=5))

Convert nullable bool? to bool

This answer is for the use case when you simply want to test the bool? in a condition. It can also be used to get a normal bool. It is an alternative I personnaly find easier to read than the coalescing operator ??.

If you want to test a condition, you can use this

bool? nullableBool = someFunction();
if(nullableBool == true)
{
    //Do stuff
}

The above if will be true only if the bool? is true.

You can also use this to assign a regular bool from a bool?

bool? nullableBool = someFunction();
bool regularBool = nullableBool == true;

witch is the same as

bool? nullableBool = someFunction();
bool regularBool = nullableBool ?? false;

How do you clear a slice in Go?

Setting the slice to nil is the best way to clear a slice. nil slices in go are perfectly well behaved and setting the slice to nil will release the underlying memory to the garbage collector.

See playground

package main

import (
    "fmt"
)

func dump(letters []string) {
    fmt.Println("letters = ", letters)
    fmt.Println(cap(letters))
    fmt.Println(len(letters))
    for i := range letters {
        fmt.Println(i, letters[i])
    }
}

func main() {
    letters := []string{"a", "b", "c", "d"}
    dump(letters)
    // clear the slice
    letters = nil
    dump(letters)
    // add stuff back to it
    letters = append(letters, "e")
    dump(letters)
}

Prints

letters =  [a b c d]
4
4
0 a
1 b
2 c
3 d
letters =  []
0
0
letters =  [e]
1
1
0 e

Note that slices can easily be aliased so that two slices point to the same underlying memory. The setting to nil will remove that aliasing.

This method changes the capacity to zero though.

How long to brute force a salted SHA-512 hash? (salt provided)

In your case, breaking the hash algorithm is equivalent to finding a collision in the hash algorithm. That means you don't need to find the password itself (which would be a preimage attack), you just need to find an output of the hash function that is equal to the hash of a valid password (thus "collision"). Finding a collision using a birthday attack takes O(2^(n/2)) time, where n is the output length of the hash function in bits.

SHA-2 has an output size of 512 bits, so finding a collision would take O(2^256) time. Given there are no clever attacks on the algorithm itself (currently none are known for the SHA-2 hash family) this is what it takes to break the algorithm.

To get a feeling for what 2^256 actually means: currently it is believed that the number of atoms in the (entire!!!) universe is roughly 10^80 which is roughly 2^266. Assuming 32 byte input (which is reasonable for your case - 20 bytes salt + 12 bytes password) my machine takes ~0,22s (~2^-2s) for 65536 (=2^16) computations. So 2^256 computations would be done in 2^240 * 2^16 computations which would take

2^240 * 2^-2 = 2^238 ~ 10^72s ~ 3,17 * 10^64 years

Even calling this millions of years is ridiculous. And it doesn't get much better with the fastest hardware on the planet computing thousands of hashes in parallel. No human technology will be able to crunch this number into something acceptable.

So forget brute-forcing SHA-256 here. Your next question was about dictionary words. To retrieve such weak passwords rainbow tables were used traditionally. A rainbow table is generally just a table of precomputed hash values, the idea is if you were able to precompute and store every possible hash along with its input, then it would take you O(1) to look up a given hash and retrieve a valid preimage for it. Of course this is not possible in practice since there's no storage device that could store such enormous amounts of data. This dilemma is known as memory-time tradeoff. As you are only able to store so many values typical rainbow tables include some form of hash chaining with intermediary reduction functions (this is explained in detail in the Wikipedia article) to save on space by giving up a bit of savings in time.

Salts were a countermeasure to make such rainbow tables infeasible. To discourage attackers from precomputing a table for a specific salt it is recommended to apply per-user salt values. However, since users do not use secure, completely random passwords, it is still surprising how successful you can get if the salt is known and you just iterate over a large dictionary of common passwords in a simple trial and error scheme. The relationship between natural language and randomness is expressed as entropy. Typical password choices are generally of low entropy, whereas completely random values would contain a maximum of entropy.

The low entropy of typical passwords makes it possible that there is a relatively high chance of one of your users using a password from a relatively small database of common passwords. If you google for them, you will end up finding torrent links for such password databases, often in the gigabyte size category. Being successful with such a tool is usually in the range of minutes to days if the attacker is not restricted in any way.

That's why generally hashing and salting alone is not enough, you need to install other safety mechanisms as well. You should use an artificially slowed down entropy-enducing method such as PBKDF2 described in PKCS#5 and you should enforce a waiting period for a given user before they may retry entering their password. A good scheme is to start with 0.5s and then doubling that time for each failed attempt. In most cases users don't notice this and don't fail much more often than three times on average. But it will significantly slow down any malicious outsider trying to attack your application.

Using IF..ELSE in UPDATE (SQL server 2005 and/or ACCESS 2007)

this should work

update table_name
  set column_b = case
                  when column_a = 1 then 'Y'
                  else null
                 end,
  set column_c = case
                  when column_a = 2 then 'Y'
                  else null
                 end,
  set column_d = case
                  when column_a = 3 then 'Y'
                  else null
                 end
where
 conditions

the question is why would you want to do that...you may want to rethink the data model. you can replace null with whatever you want.

Create zip file and ignore directory structure

Use the -j option:

   -j     Store  just the name of a saved file (junk the path), and do not
          store directory names. By default, zip will store the full  path
          (relative to the current path).

How do I align a label and a textarea?

Align the text area box to the label, not the label to the text area,

label {
    width: 180px;
    display: inline-block;
}

textarea{
    vertical-align: middle;
}

<label for="myfield">Label text</label><textarea id="myfield" rows="5" cols="30"></textarea>

Practical uses for AtomicInteger

In Java 8 atomic classes have been extended with two interesting functions:

  • int getAndUpdate(IntUnaryOperator updateFunction)
  • int updateAndGet(IntUnaryOperator updateFunction)

Both are using the updateFunction to perform update of the atomic value. The difference is that the first one returns old value and the second one return the new value. The updateFunction may be implemented to do more complex "compare and set" operations than the standard one. For example it can check that atomic counter doesn't go below zero, normally it would require synchronization, and here the code is lock-free:

    public class Counter {

      private final AtomicInteger number;

      public Counter(int number) {
        this.number = new AtomicInteger(number);
      }

      /** @return true if still can decrease */
      public boolean dec() {
        // updateAndGet(fn) executed atomically:
        return number.updateAndGet(n -> (n > 0) ? n - 1 : n) > 0;
      }
    }

The code is taken from Java Atomic Example.

How do I parse a string with a decimal point to a double?

string testString1 = "2,457";
string testString2 = "2.457";    
double testNum = 0.5;
char decimalSepparator;
decimalSepparator = testNum.ToString()[1];

Console.WriteLine(double.Parse(testString1.Replace('.', decimalSepparator).Replace(',', decimalSepparator)));
Console.WriteLine(double.Parse(testString2.Replace('.', decimalSepparator).Replace(',', decimalSepparator)));

Add to Array jQuery

For JavaScript arrays, you use push().

var a = [];
a.push(12);
a.push(32);

For jQuery objects, there's add().

$('div.test').add('p.blue');

Note that while push() modifies the original array in-place, add() returns a new jQuery object, it does not modify the original one.

Set Label Text with JQuery

You can try:

<label id ="label_id"></label>
 $("#label_id").html('value');

How to make a PHP SOAP call using the SoapClient class

First initialize webservices:

$client = new SoapClient("http://example.com/webservices?wsdl");

Then set and pass the parameters:

$params = array (
    "arg0" => $contactid,
    "arg1" => $desc,
    "arg2" => $contactname
);

$response = $client->__soapCall('methodname', array($params));

Note that the method name is available in WSDL as operation name, e.g.:

<operation name="methodname">

AttributeError: 'str' object has no attribute 'strftime'

you should change cr_date(str) to datetime object then you 'll change the date to the specific format:

cr_date = '2013-10-31 18:23:29.000227'
cr_date = datetime.datetime.strptime(cr_date, '%Y-%m-%d %H:%M:%S.%f')
cr_date = cr_date.strftime("%m/%d/%Y")

pass parameter by link_to ruby on rails

The above did not work for me but this did

<%= link_to "text_to_show_in_url", action_controller_path(:gender => "male", :param2=> "something_else") %>

How to stop the Timer in android?

I had a similar problem and it was caused by the placement of the Timer initialisation.

It was placed in a method that was invoked oftener.

Try this:

Timer waitTimer;

  void exampleMethod() {

   if (waitTimer == null ) {
    //initialize your Timer here
    ...
   }

The "cancel()" method only canceled the latest Timer. The older ones were ignored an didn't stop running.

d3.select("#element") not working when code above the html element

Not enough reputation to comment yet so I'll just put this here:

To expand on Micah's answer - the browser runs your code top to bottom, so if you write:

<div id="chart"></div>
<script>var svg = d3.select("#chart").append("svg:svg");</script>

The browser will create a div with id "chart", and then run your script, which will try to find that div, and, hurray, success.

Otherwise if you write:

<script>var svg = d3.select("#chart").append("svg:svg");</script>
<div id="chart"></div>

The browser runs your script, and tries to find a div with id chart, but it hasn't been created yet so it fails.

THEN the browser creates a div with id "chart".

Where can I find the assembly System.Web.Extensions dll?

I had this issue when converting an older project to use a new version of Visual Studio. Upon conversion, the project target framework was set to 2.0

I was able to solve this issue by changing the target framework to be 3.5.

Can Android do peer-to-peer ad-hoc networking?

my friend and I are currently developing a java library implementing the AODV protocol (multihop routing suitable for mobile networks), in our bachelor thesis. The final 'product' includes a easy way to create/join an adhoc network on several android devices and an interface through the library, to send and receive messages. Unfortunately each type of phone such as hero, nexsus one... have a phonedepended way for createing a adhoc network so currently we are only supporting a few phones).

this means that once this project is finished, people with rooted phones can implement their distributed applications (file sharing, games, ...) by simply including the library .jar file in their android projects.

it's all open source by the way

http://code.google.com/p/adhoc-on-android/

Communicating between a fragment and an activity - best practices

There is the latest techniques to communicate fragment to activity without any interface follow the steps Step 1- Add the dependency in gradle

implementation 'androidx.fragment:fragment:1.3.0-rc01'

how to check if string contains '+' character

Why not just:

int plusIndex = s.indexOf("+");
if (plusIndex != -1) {
    String before = s.substring(0, plusIndex);
    // Use before
}

It's not really clear why your original version didn't work, but then you didn't say what actually happened. If you want to split not using regular expressions, I'd personally use Guava:

Iterable<String> bits = Splitter.on('+').split(s);
String firstPart = Iterables.getFirst(bits, "");

If you're going to use split (either the built-in version or Guava) you don't need to check whether it contains + first - if it doesn't there'll only be one result anyway. Obviously there's a question of efficiency, but it's simpler code:

// Calling split unconditionally
String[] parts = s.split("\\+");
s = parts[0];

Note that writing String[] parts is preferred over String parts[] - it's much more idiomatic Java code.

How to loop and render elements in React-native?

If u want a direct/ quick away, without assing to variables:

{
 urArray.map((prop, key) => {
     console.log(emp);
     return <Picker.Item label={emp.Name} value={emp.id} />;
 })
}

Receive JSON POST with PHP

$data = file_get_contents('php://input');
echo $data;

This worked for me.

Get bitcoin historical data

Coinbase has a REST API that gives you access to historical prices from their website. The data seems to show the Coinbase spot price (in USD) about every ten minutes.

Results are returned in CSV format. You must query the page number you want through the API. There are 1000 results (or price points) per page. That's about 7 days' worth of data per page.

Android findViewById() in Custom View

Change your Method as following and check it will work

private void initViews() {
    inflater = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    inflater.inflate(R.layout.id_number_edit_text_custom, this, true);
    View view = (View) inflater.inflate(R.layout.main, null);
    editText = (EditText) view.findViewById(R.id.id_number_custom);
    loadButton = (ImageButton) view.findViewById(R.id.load_data_button);
    loadButton.setVisibility(RelativeLayout.INVISIBLE);
    loadData();
} 

How to convert a single char into an int

#include<iostream>
#include<stdlib>
using namespace std;

void main()
{
     char ch;
     int x;
     cin >> ch;
     x = char (ar[1]);
     cout << x;
}

MongoDB: Is it possible to make a case-insensitive query?

TL;DR

Correct way to do this in mongo

Do not Use RegExp

Go natural And use mongodb's inbuilt indexing , search

Step 1 :

db.articles.insert(
   [
     { _id: 1, subject: "coffee", author: "xyz", views: 50 },
     { _id: 2, subject: "Coffee Shopping", author: "efg", views: 5 },
     { _id: 3, subject: "Baking a cake", author: "abc", views: 90  },
     { _id: 4, subject: "baking", author: "xyz", views: 100 },
     { _id: 5, subject: "Café Con Leche", author: "abc", views: 200 },
     { _id: 6, subject: "???????", author: "jkl", views: 80 },
     { _id: 7, subject: "coffee and cream", author: "efg", views: 10 },
     { _id: 8, subject: "Cafe con Leche", author: "xyz", views: 10 }
   ]
)
 

Step 2 :

Need to create index on whichever TEXT field you want to search , without indexing query will be extremely slow

db.articles.createIndex( { subject: "text" } )

step 3 :

db.articles.find( { $text: { $search: "coffee",$caseSensitive :true } } )  //FOR SENSITIVITY
db.articles.find( { $text: { $search: "coffee",$caseSensitive :false } } ) //FOR INSENSITIVITY


 

GROUP BY without aggregate function

Let me give some examples.

Consider this data.

CREATE TABLE DATASET ( VAL1 CHAR ( 1 CHAR ),
                   VAL2 VARCHAR2 ( 10 CHAR ),
                   VAL3 NUMBER );

INSERT INTO
      DATASET ( VAL1, VAL2, VAL3 )
VALUES
      ( 'b', 'b-details', 2 );

INSERT INTO
      DATASET ( VAL1, VAL2, VAL3 )
VALUES
      ( 'a', 'a-details', 1 );

INSERT INTO
      DATASET ( VAL1, VAL2, VAL3 )
VALUES
      ( 'c', 'c-details', 3 );

INSERT INTO
      DATASET ( VAL1, VAL2, VAL3 )
VALUES
      ( 'a', 'dup', 4 );

INSERT INTO
      DATASET ( VAL1, VAL2, VAL3 )
VALUES
      ( 'c', 'c-details', 5 );

COMMIT;

Whats there in table now

SELECT * FROM DATASET;

VAL1 VAL2             VAL3
---- ---------- ----------
b    b-details           2
a    a-details           1
c    c-details           3
a    dup                 4
c    c-details           5

5 rows selected.

--aggregate with group by

SELECT
      VAL1,
      COUNT ( * )
FROM
      DATASET A
GROUP BY
      VAL1;

VAL1   COUNT(*)
---- ----------
b             1
a             2
c             2

3 rows selected.

--aggregate with group by multiple columns but select partial column

SELECT
      VAL1,
      COUNT ( * )
FROM
      DATASET A
GROUP BY
      VAL1,
      VAL2;

VAL1  
---- 
b             
c             
a             
a             

4 rows selected.

--No aggregate with group by multiple columns

SELECT
      VAL1,
      VAL2
FROM
      DATASET A
GROUP BY
      VAL1,
      VAL2;

    VAL1  
    ---- 
    b    b-details
    c    c-details
    a    dup
    a    a-details

    4 rows selected.

--No aggregate with group by multiple columns

SELECT
      VAL1
FROM
      DATASET A
GROUP BY
      VAL1,
      VAL2;

    VAL1  
    ---- 
    b
    c
    a
    a

    4 rows selected.

You have N columns in select (excluding aggregations), then you should have N or N+x columns

Returning a boolean from a Bash function

It might work if you rewrite this function myfun(){ ... return 0; else return 1; fi;} as this function myfun(){ ... return; else false; fi;}. That is if false is the last instruction in the function you get false result for whole function but return interrupts function with true result anyway. I believe it's true for my bash interpreter at least.

gcc makefile error: "No rule to make target ..."

In my case, it was due to me calling the Makefile: MAKEFILE (all caps)

How to get the date 7 days earlier date from current date in Java

You can use this to continue using the type Date and a more legible code, if you preffer:

import org.apache.commons.lang.time.DateUtils;
...
Date yourDate = DateUtils.addDays(new Date(), *days here*);

Typescript : Property does not exist on type 'object'

If your object could contain any key/value pairs, you could declare an interface called keyable like :

interface keyable {
    [key: string]: any  
}

then use it as follows :

let countryProviders: keyable[];

or

let countryProviders: Array<keyable>;

Radio button checked event handling

You can simply use the method change of JQuery to get the value of the current radio checked with the following code:

$(document).on('change', '[type="radio"]', function() {
    var currentlyValue = $(this).val(); // Get the radio checked value
        
    alert('Currently value: '+currentlyValue); // Show a alert with the current value
});

You can change the selector '[type="radio"]' for a class or id that you want.

Query to list all stored procedures

I've tweaked LostCajun's excellent post above to exclude system stored procedures. I also removed "Extract." from the code because I couldn't figure out what it's for and it gave me errors. The "fetch next" statement inside the loop also needed an "into" clause.

use <<databasename>>
go

declare @aQuery nvarchar(1024);
declare @spName nvarchar(64);
declare allSP cursor for
    select p.name  
    from sys.procedures p 
    where p.type_desc = 'SQL_STORED_PROCEDURE' 
    and LEFT(p.name,3) NOT IN ('sp_','xp_','ms_')
    order by p.name;
open allSP;
fetch next from allSP into @spName;
while (@@FETCH_STATUS = 0)
begin
    set @aQuery = 'sp_helptext [' + @spName + ']';
    exec sp_executesql @aQuery;
    fetch next from allSP into @spName;
end;
close allSP;
deallocate allSP;

Appending items to a list of lists in python

import csv
cols = [' V1', ' I1'] # define your columns here, check the spaces!
data = [[] for col in cols] # this creates a list of **different** lists, not a list of pointers to the same list like you did in [[]]*len(positions) 
with open('data.csv', 'r') as f:
    for rec in csv.DictReader(f):
        for l, col in zip(data, cols):
            l.append(float(rec[col]))
print data

# [[3.0, 3.0], [0.01, 0.01]]

Passive Link in Angular 2 - <a href=""> equivalent

I wonder why no one is suggesting routerLink and routerLinkActive (Angular 7)

<a [routerLink]="[ '/resources' ]" routerLinkActive="currentUrl!='/resources'">

I removed the href and now using this. When using href, it was going to the base url or reloading the same route again.

Call method in directive controller from other controller

This is an interesting question, and I started thinking about how I would implement something like this.

I came up with this (fiddle);

Basically, instead of trying to call a directive from a controller, I created a module to house all the popdown logic:

var PopdownModule = angular.module('Popdown', []);

I put two things in the module, a factory for the API which can be injected anywhere, and the directive for defining the behavior of the actual popdown element:

The factory just defines a couple of functions success and error and keeps track of a couple of variables:

PopdownModule.factory('PopdownAPI', function() {
    return {
        status: null,
        message: null,
        success: function(msg) {
            this.status = 'success';
            this.message = msg;
        },
        error: function(msg) {
            this.status = 'error';
            this.message = msg;
        },
        clear: function() {
            this.status = null;
            this.message = null;
        }
    }
});

The directive gets the API injected into its controller, and watches the api for changes (I'm using bootstrap css for convenience):

PopdownModule.directive('popdown', function() {
    return {
        restrict: 'E',
        scope: {},
        replace: true,
        controller: function($scope, PopdownAPI) {
            $scope.show = false;
            $scope.api = PopdownAPI;

            $scope.$watch('api.status', toggledisplay)
            $scope.$watch('api.message', toggledisplay)

            $scope.hide = function() {
                $scope.show = false;
                $scope.api.clear();
            };

            function toggledisplay() {
                $scope.show = !!($scope.api.status && $scope.api.message);               
            }
        },
        template: '<div class="alert alert-{{api.status}}" ng-show="show">' +
                  '  <button type="button" class="close" ng-click="hide()">&times;</button>' +
                  '  {{api.message}}' +
                  '</div>'
    }
})

Then I define an app module that depends on Popdown:

var app = angular.module('app', ['Popdown']);

app.controller('main', function($scope, PopdownAPI) {
    $scope.success = function(msg) { PopdownAPI.success(msg); }
    $scope.error   = function(msg) { PopdownAPI.error(msg); }
});

And the HTML looks like:

<html ng-app="app">
    <body ng-controller="main">
        <popdown></popdown>
        <a class="btn" ng-click="success('I am a success!')">Succeed</a>
        <a class="btn" ng-click="error('Alas, I am a failure!')">Fail</a>
    </body>
</html>

I'm not sure if it's completely ideal, but it seemed like a reasonable way to set up communication with a global-ish popdown directive.

Again, for reference, the fiddle.

How to get date, month, year in jQuery UI datepicker?

what about that simple way)

$(document).ready ->
 $('#datepicker').datepicker( dateFormat: 'yy-mm-dd',  onSelect: (dateStr) ->
    alert dateStr # yy-mm-dd
    #OR
    alert $("#datepicker").val(); # yy-mm-dd

No authenticationScheme was specified, and there was no DefaultChallengeScheme found with default authentification and custom authorization

When I used policy before I set the default authentication scheme into it as well. I had modified the DefaultPolicy so it was slightly different. However the same should work for add policy as well.

services.AddAuthorization(options =>
        {
            options.AddPolicy(DefaultAuthorizedPolicy, policy =>
            {
                policy.Requirements.Add(new TokenAuthRequirement());
                policy.AuthenticationSchemes = new List<string>()
                                {
                                    CookieAuthenticationDefaults.AuthenticationScheme
                                }
            });
        });

Do take into consideration that by Default AuthenticationSchemes property uses a read only list. I think it would be better to implement that instead of List as well.

How to have EditText with border in Android Lollipop

You can use a drawable. Create a drawable layout file in your drawable folder. Paste this code. You can as well modify it - border.xml.

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<stroke
    android:width="1dp"
    android:color="@color/divider" />
<solid
    android:color="#00FFFFFF"
    android:paddingLeft="10dp"
    android:paddingTop="10dp"/>
<padding
    android:left="10dp"
    android:top="10dp"
    android:right="10dp"
    android:bottom="10dp" />
</shape>

in your EditText view, add

android:background="@drawable/border"

How to check if a string contains an element from a list in Python

Use a generator together with any, which short-circuits on the first True:

if any(ext in url_string for ext in extensionsToCheck):
    print(url_string)

EDIT: I see this answer has been accepted by OP. Though my solution may be "good enough" solution to his particular problem, and is a good general way to check if any strings in a list are found in another string, keep in mind that this is all that this solution does. It does not care WHERE the string is found e.g. in the ending of the string. If this is important, as is often the case with urls, you should look to the answer of @Wladimir Palant, or you risk getting false positives.

CURL Command Line URL Parameters

Felipsmartins is correct.

It is worth mentioning that it is because you cannot really use the -d/--data option if this is not a POST request. But this is still possible if you use the -G option.

Which means you can do this:

curl -X DELETE -G 'http://localhost:5000/locations' -d 'id=3'

Here it is a bit silly but when you are on the command line and you have a lot of parameters, it is a lot tidier.

I am saying this because cURL commands are usually quite long, so it is worth making it on more than one line escaping the line breaks.

curl -X DELETE -G \
'http://localhost:5000/locations' \
-d id=3 \
-d name=Mario \
-d surname=Bros

This is obviously a lot more comfortable if you use zsh. I mean when you need to re-edit the previous command because zsh lets you go line by line. (just saying)

Hope it helps.

Moment JS start and end of given month

_x000D_
_x000D_
const year = 2014;_x000D_
const month = 09;_x000D_
_x000D_
// months start at index 0 in momentjs, so we subtract 1_x000D_
const startDate = moment([year, month - 1, 01]).format("YYYY-MM-DD");_x000D_
_x000D_
// get the number of days for this month_x000D_
const daysInMonth = moment(startDate).daysInMonth();_x000D_
_x000D_
// we are adding the days in this month to the start date (minus the first day)_x000D_
const endDate = moment(startDate).add(daysInMonth - 1, 'days').format("YYYY-MM-DD");_x000D_
_x000D_
console.log(`start date: ${startDate}`);_x000D_
console.log(`end date:   ${endDate}`);
_x000D_
<script_x000D_
src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.20.1/moment.min.js">_x000D_
</script>
_x000D_
_x000D_
_x000D_

How to test whether a service is running from the command line

Just to add on to the list if you are using Powershell.

sc.exe query "ServiceName" | findstr RUNNING

The command below does not work because sc is an alias to Set-Content within Powershell.

sc query "ServiceName" | findstr RUNNING

find also does not work on Powershell for some reason unknown to me.

sc.exe query "ServiceName" | find RUNNING

How to distinguish mouse "click" and "drag"

For a public action on an OSM map (position a marker on click) the question was: 1) how to determine the duration of mouse down->up (you can't imagine creating a new marker for each click) and 2) did the mouse move during down->up (i.e user is dragging the map).

const map = document.getElementById('map');

map.addEventListener("mousedown", position); 
map.addEventListener("mouseup", calculate);

let posX, posY, endX, endY, t1, t2, action;

function position(e) {

  posX = e.clientX;
  posY = e.clientY;
  t1 = Date.now();

}

function calculate(e) {

  endX = e.clientX;
  endY = e.clientY;
  t2 = (Date.now()-t1)/1000;
  action = 'inactive';

  if( t2 > 0.5 && t2 < 1.5) { // Fixing duration of mouse down->up

      if( Math.abs( posX-endX ) < 5 && Math.abs( posY-endY ) < 5 ) { // 5px error on mouse pos while clicking
         action = 'active';
         // --------> Do something
      }
  }
  console.log('Down = '+posX + ', ' + posY+'\nUp = '+endX + ', ' + endY+ '\nAction = '+ action);    

}

How to get row number in dataframe in Pandas?

You can simply use shape method df[df['LastName'] == 'Smith'].shape

Output
(1,1)

Which indicates 1 row and 1 column. This way you can get the idea of whole datasets

Let me explain the above code DataframeName[DataframeName['Column_name'] == 'Value to match in column']

Angular no provider for NameService

Hi , You can use this in your .ts file :

first import your service in this .ts file:

import { Your_Service_Name } from './path_To_Your_Service_Name';

Then in the same file you can add providers: [Your_Service_Name] :

 @Component({
      selector: 'my-app',
      providers: [Your_Service_Name],
      template: `
        <h1>Hello World</h1> `   
    })

Download a file with Android, and showing the progress in a ProgressDialog

I am adding another answer for other solution I am using now because Android Query is so big and unmaintained to stay healthy. So i moved to this https://github.com/amitshekhariitbhu/Fast-Android-Networking.

    AndroidNetworking.download(url,dirPath,fileName).build()
      .setDownloadProgressListener(new DownloadProgressListener() {
        public void onProgress(long bytesDownloaded, long totalBytes) {
            bar.setMax((int) totalBytes);
            bar.setProgress((int) bytesDownloaded);
        }
    }).startDownload(new DownloadListener() {
        public void onDownloadComplete() {
            ...
        }

        public void onError(ANError error) {
            ...
        }
    });

How do I add an image to a JButton

I did only one thing and it worked for me .. check your code is this method there ..

setResizable(false);

if it false make it true and it will work just fine .. I hope it helped ..

How do you use "git --bare init" repository?

The general practice is to have the central repository to which you push as a bare repo.

If you have SVN background, you can relate an SVN repo to a Git bare repo. It doesn't have the files in the repo in the original form. Whereas your local repo will have the files that form your "code" in addition.

You need to add a remote to the bare repo from your local repo and push your "code" to it.

It will be something like:

git remote add central <url> # url will be ssh based for you
git push --all central

deny directory listing with htaccess

Options -Indexes should work to prevent directory listings.

If you are using a .htaccess file make sure you have at least the "allowoverride options" setting in your main apache config file.

jQuery .load() call doesn't execute JavaScript in loaded HTML file

$("#images").load(location.href+" #images",function(){
    $.getScript("js/productHelper.js"); 
});

How to create JNDI context in Spring Boot with Embedded Tomcat Container

Have you tried @Lazy loading the datasource? Because you're initialising your embedded Tomcat container within the Spring context, you have to delay the initialisation of your DataSource (until the JNDI vars have been setup).

N.B. I haven't had a chance to test this code yet!

@Lazy
@Bean(destroyMethod="")
public DataSource jndiDataSource() throws IllegalArgumentException, NamingException {
    JndiObjectFactoryBean bean = new JndiObjectFactoryBean();
    bean.setJndiName("java:comp/env/jdbc/myDataSource");
    bean.setProxyInterface(DataSource.class);
    //bean.setLookupOnStartup(false);
    bean.afterPropertiesSet();
    return (DataSource)bean.getObject();
}

You may also need to add the @Lazy annotation wherever the DataSource is being used. e.g.

@Lazy
@Autowired
private DataSource dataSource;

Session 'app': Error Installing APK

It was written above: in my case it was just out of memory on device storage. Add more empty space - and error will disappear

Adding value labels on a matplotlib bar chart

If you want to just label the data points above the bar, you could use plt.annotate()

My code:

import numpy as np
import matplotlib.pyplot as plt

n = [1,2,3,4,5,]
s = [i**2 for i in n]
line = plt.bar(n,s)
plt.xlabel('Number')
plt.ylabel("Square")

for i in range(len(s)):
    plt.annotate(str(s[i]), xy=(n[i],s[i]), ha='center', va='bottom')

plt.show()

By specifying a horizontal and vertical alignment of 'center' and 'bottom' respectively one can get centered annotations.

a labelled bar chart

What is a Sticky Broadcast?

A normal broadcast Intent is not available anymore after is was send and processed by the system. If you use the sendStickyBroadcast(Intent) method, the Intent is sticky, meaning the Intent you are sending stays around after the broadcast is complete.

you refer to my blog:enter link description here

How can I generate Unix timestamps?

In Perl:

>> time
=> 1335552733

How do you comment an MS-access Query?

The first answer mentioned how to get the description property programatically. If you're going to bother with program anyway, since the comments in the query are so kludgy, instead of trying to put the comments in the query, maybe it's better to put them in a program and use the program to make all your queries

Dim dbs As DAO.Database
Dim qry As DAO.QueryDef

Set dbs = CurrentDb
'put your comments wherever in your program makes the most sense
dbs.QueryDefs("qryName").SQL = "SELECT whatever.fields FROM whatever_table;"
DoCmd.OpenQuery "qryname"

For..In loops in JavaScript - key value pairs

Below is an example that gets as close as you get.

for(var key in data){
  var value = data[key];    
  //your processing here
}

If you're using jQuery see: http://api.jquery.com/jQuery.each/

How to get difference between two rows for a column field?

Does SQL Server support analytic functions?

select   rowint,
         value,
         value - lag(value) over (order by rowint) diff
from     myTable
order by rowint
/

Replacement for deprecated sizeWithFont: in iOS 7?

I created a category to handle this problem, here it is :

#import "NSString+StringSizeWithFont.h"

@implementation NSString (StringSizeWithFont)

- (CGSize) sizeWithMyFont:(UIFont *)fontToUse
{
    if ([self respondsToSelector:@selector(sizeWithAttributes:)])
    {
        NSDictionary* attribs = @{NSFontAttributeName:fontToUse};
        return ([self sizeWithAttributes:attribs]);
    }
    return ([self sizeWithFont:fontToUse]);
}

This way you only have to find/replace sizeWithFont: with sizeWithMyFont: and you're good to go.

Error:Conflict with dependency 'com.google.code.findbugs:jsr305'

For react-native-firebase, adding this to app/build.gradle dependencies section made it work for me:

implementation('com.squareup.okhttp3:okhttp:3.12.1') { force = true }
implementation('com.squareup.okio:okio:1.15.0') { force = true }
implementation('com.google.code.findbugs:jsr305:3.0.2') { force = true}

How do I run a batch file from my Java Application?

The following is working fine:

String path="cmd /c start d:\\sample\\sample.bat";
Runtime rn=Runtime.getRuntime();
Process pr=rn.exec(path);

Running java with JAVA_OPTS env variable has no effect

I don't know of any JVM that actually checks the JAVA_OPTS environment variable. Usually this is used in scripts which launch the JVM and they usually just add it to the java command-line.

The key thing to understand here is that arguments to java that come before the -jar analyse.jar bit will only affect the JVM and won't be passed along to your program. So, modifying the java line in your script to:

java $JAVA_OPTS -jar analyse.jar $*

Should "just work".

How to quickly form groups (quartiles, deciles, etc) by ordering column(s) in a data frame

Adapting dplyr::ntile to take advantage of data.table optimizations provides a faster solution.

library(data.table)
setDT(temp)
temp[order(value) , quartile := floor( 1 + 4 * (.I-1) / .N)]

Probably doesn't qualify as cleaner, but it's faster and one-line.

Timing on bigger data set

Comparing this solution to ntile and cut for data.table as proposed by @docendo_discimus and @MichaelChirico.

library(microbenchmark)
library(dplyr)

set.seed(123)

n <- 1e6
temp <- data.frame(name=sample(letters, size=n, replace=TRUE), value=rnorm(n))
setDT(temp)

microbenchmark(
    "ntile" = temp[, quartile_ntile := ntile(value, 4)],
    "cut" = temp[, quartile_cut := cut(value,
                                       breaks = quantile(value, probs = seq(0, 1, by=1/4)),
                                       labels = 1:4, right=FALSE)],
    "dt_ntile" = temp[order(value), quartile_ntile_dt := floor( 1 + 4 * (.I-1)/.N)]
)

Gives:

Unit: milliseconds
     expr      min       lq     mean   median       uq      max neval
    ntile 608.1126 647.4994 670.3160 686.5103 691.4846 712.4267   100
      cut 369.5391 373.3457 375.0913 374.3107 376.5512 385.8142   100
 dt_ntile 117.5736 119.5802 124.5397 120.5043 124.5902 145.7894   100

How do I upload a file to an SFTP server in C# (.NET)?

Unfortunately, it's not in the .NET Framework itself. My wish is that you could integrate with FileZilla, but I don't think it exposes an interface. They do have scripting I think, but it won't be as clean obviously.

I've used CuteFTP in a project which does SFTP. It exposes a COM component which I created a .NET wrapper around. The catch, you'll find, is permissions. It runs beautifully under the Windows credentials which installed CuteFTP, but running under other credentials requires permissions to be set in DCOM.

Proper use of errors

Simple solution to emit and show message by Exception.

try {
  throw new TypeError("Error message");
}
catch (e){
  console.log((<Error>e).message);//conversion to Error type
}

Caution

Above is not a solution if we don't know what kind of error can be emitted from the block. In such cases type guards should be used and proper handling for proper error should be done - take a look on @Moriarty answer.

How to zip a whole folder using PHP

This is a function that zips a whole folder and its contents in to a zip file and you can use it simple like this :

addzip ("path/folder/" , "/path2/folder.zip" );

function :

// compress all files in the source directory to destination directory 
    function create_zip($files = array(), $dest = '', $overwrite = false) {
    if (file_exists($dest) && !$overwrite) {
        return false;
    }
    if (($files)) {
        $zip = new ZipArchive();
        if ($zip->open($dest, $overwrite ? ZIPARCHIVE::OVERWRITE : ZIPARCHIVE::CREATE) !== true) {
            return false;
        }
        foreach ($files as $file) {
            $zip->addFile($file, $file);
        }
        $zip->close();
        return file_exists($dest);
    } else {
        return false;
    }
}

function addzip($source, $destination) {
    $files_to_zip = glob($source . '/*');
    create_zip($files_to_zip, $destination);
    echo "done";
}

take(1) vs first()

Operators first() and take(1) aren't the same.

The first() operator takes an optional predicate function and emits an error notification when no value matched when the source completed.

For example this will emit an error:

import { EMPTY, range } from 'rxjs';
import { first, take } from 'rxjs/operators';

EMPTY.pipe(
  first(),
).subscribe(console.log, err => console.log('Error', err));

... as well as this:

range(1, 5).pipe(
  first(val => val > 6),
).subscribe(console.log, err => console.log('Error', err));

While this will match the first value emitted:

range(1, 5).pipe(
  first(),
).subscribe(console.log, err => console.log('Error', err));

On the other hand take(1) just takes the first value and completes. No further logic is involved.

range(1, 5).pipe(
  take(1),
).subscribe(console.log, err => console.log('Error', err));

Then with empty source Observable it won't emit any error:

EMPTY.pipe(
  take(1),
).subscribe(console.log, err => console.log('Error', err));

Jan 2019: Updated for RxJS 6

Partial Dependency (Databases)

I hope this explaination gives a more intuitive appeal to dependency than the answers previously given.

Functional Dependency

An analysis of dependency operates on the attribute level, i.e. one or more attribute is determined by another attribute, it comes before the concept of keys. 'The role of a key is based on the concept of determination. 'Determination is the state in which knowing the value of one attribute makes it possible to determine the value of another.' Database Systems 12ed

Functional dependency is when one or more attributes determine one or more attributes. For instance:

Social Security Number -> First Name, Last Name.

However, by definition of functional dependency:

(SSN, First Name) -> Last Name

This is also a valid functional dependency. The determinants (The attribute that which determines another attribution) are called super key.

Full Functional Dependency

Thus, as a subset of functional dependency, there is the concept of full functional dependency, where the bare minimal determinant is considered. We refer those bare minimal determinants collectively as one candidate key (weird linguistic quirk in my opinion, like the concept of vector).

Partial Functional Dependency

However, sometimes one of the attributes in the candidate key is sufficient to determine another attribute(s), BUT not all, in a relation (a table with no rows). That, is when you have a partial functional dependency within a relation.

Cloning specific branch

You can use the following flags --single-branch && --depth to download the specific branch and to limit the amount of history which will be downloaded.

You will clone the repo from a certain point in time and only for the given branch

git clone -b <branch> --single-branch <url> --depth <number of commits>

--[no-]single-branch


Clone only the history leading to the tip of a single branch, either specified by the --branch option or the primary branch remote’s HEAD points at.

Further fetches into the resulting repository will only update the remote-tracking branch for the branch this option was used for the initial cloning. If the HEAD at the remote did not point at any branch when --single-branch clone was made, no remote-tracking branch is created.


--depth

Create a shallow clone with a history truncated to the specified number of commits

What is C# analog of C++ std::pair?

On order to get the above to work (I needed a pair as the key of a dictionary). I had to add:

    public override Boolean Equals(Object o)
    {
        Pair<T, U> that = o as Pair<T, U>;
        if (that == null)
            return false;
        else
            return this.First.Equals(that.First) && this.Second.Equals(that.Second);
    }

and once I did that I also added

    public override Int32 GetHashCode()
    {
        return First.GetHashCode() ^ Second.GetHashCode();
    }

to suppress a compiler warning.

Change fill color on vector asset in Android Studio

For those not using an ImageView, the following worked for me on a plain View (and hence the behaviour should replicate on any kind of view)

<View
    android:background="@drawable/ic_reset"
    android:backgroundTint="@color/colorLightText" />

System has not been booted with systemd as init system (PID 1). Can't operate

Instead, use: sudo service redis-server start

I had the same problem, stopping/starting other services from within Ubuntu on WSL. This worked, where systemctl did not.

And one could reasonably wonder, "how would you know that the service name was 'redis-server'?" You can see them using service --status-all

Reading in from System.in - Java

You can use System.in to read from the standard input. It works just like entering it from a keyboard. The OS handles going from file to standard input.

class MyProg {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.println("Printing the file passed in:");
        while(sc.hasNextLine()) System.out.println(sc.nextLine());
    }
}

Rebasing a Git merge commit

Given that I just lost a day trying to figure this out and actually found a solution with the help of a coworker, I thought I should chime in.

We have a large code base and we have to deal with 2 branch heavily being modified at the same time. There is a main branch and a secondary branch if you which.

While I merge the secondary branch into the main branch, work continues in the main branch and by the time i'm done, I can't push my changes because they are incompatible.

I therefore need to "rebase" my "merge".

This is how we finally did it :

1) make note of the SHA. ex.: c4a924d458ea0629c0d694f1b9e9576a3ecf506b

git log -1

2) Create the proper history but this will break the merge.

git rebase -s ours --preserve-merges origin/master

3) make note of the SHA. ex.: 29dd8101d78

git log -1

4) Now reset to where you were before

git reset c4a924d458ea0629c0d694f1b9e9576a3ecf506b --hard

5) Now merge the current master into your working branch

git merge origin/master
git mergetool
git commit -m"correct files

6) Now that you have the right files, but the wrong history, get the right history on top of your change with :

git reset 29dd8101d78 --soft

7) And then --amend the results in your original merge commit

git commit --amend

Voila!

How do I convert strings in a Pandas data frame to a 'date' data type?

Essentially equivalent to @waitingkuo, but I would use to_datetime here (it seems a little cleaner, and offers some additional functionality e.g. dayfirst):

In [11]: df
Out[11]:
   a        time
0  1  2013-01-01
1  2  2013-01-02
2  3  2013-01-03

In [12]: pd.to_datetime(df['time'])
Out[12]:
0   2013-01-01 00:00:00
1   2013-01-02 00:00:00
2   2013-01-03 00:00:00
Name: time, dtype: datetime64[ns]

In [13]: df['time'] = pd.to_datetime(df['time'])

In [14]: df
Out[14]:
   a                time
0  1 2013-01-01 00:00:00
1  2 2013-01-02 00:00:00
2  3 2013-01-03 00:00:00

Handling ValueErrors
If you run into a situation where doing

df['time'] = pd.to_datetime(df['time'])

Throws a

ValueError: Unknown string format

That means you have invalid (non-coercible) values. If you are okay with having them converted to pd.NaT, you can add an errors='coerce' argument to to_datetime:

df['time'] = pd.to_datetime(df['time'], errors='coerce')

How to increase Neo4j's maximum file open limit (ulimit) in Ubuntu?

You could alter the init script for neo4j to do a ulimit -n 40000 before running neo4j.

However, I can't help but feel you are barking up the wrong tree. Does neo4j legitimately need more than 10,000 open file descriptors? This sounds very much like a bug in neo4j or the way you are using it. I would try to address that.

"Continue" (to next iteration) on VBScript

We can use a separate function for performing a continue statement work. suppose you have following problem:

for i=1 to 10

if(condition) then   'for loop body'
contionue
End If

Next

Here we will use a function call for for loop body:

for i=1 to 10
Call loopbody()
next

function loopbody()

if(condition) then   'for loop body'
Exit Function
End If

End Function

loop will continue for function exit statement....

How to print the ld(linker) search path

On Linux, you can use ldconfig, which maintains the ld.so configuration and cache, to print out the directories search by ld.so with

ldconfig -v 2>/dev/null | grep -v ^$'\t'

ldconfig -v prints out the directories search by the linker (without a leading tab) and the shared libraries found in those directories (with a leading tab); the grep gets the directories. On my machine, this line prints out

/usr/lib64/atlas:
/usr/lib/llvm:
/usr/lib64/llvm:
/usr/lib64/mysql:
/usr/lib64/nvidia:
/usr/lib64/tracker-0.12:
/usr/lib/wine:
/usr/lib64/wine:
/usr/lib64/xulrunner-2:
/lib:
/lib64:
/usr/lib:
/usr/lib64:
/usr/lib64/nvidia/tls: (hwcap: 0x8000000000000000)
/lib/i686: (hwcap: 0x0008000000000000)
/lib64/tls: (hwcap: 0x8000000000000000)
/usr/lib/sse2: (hwcap: 0x0000000004000000)
/usr/lib64/tls: (hwcap: 0x8000000000000000)
/usr/lib64/sse2: (hwcap: 0x0000000004000000)

The first paths, without hwcap in the line, are either built-in or read from /etc/ld.so.conf. The linker can then search additional directories under the basic library search path, with names like sse2 corresponding to additional CPU capabilities. These paths, with hwcap in the line, can contain additional libraries tailored for these CPU capabilities.

One final note: using -p instead of -v above searches the ld.so cache instead.

How to change the color of the axis, ticks and labels for a plot in matplotlib

  • For those using pandas.DataFrame.plot(), matplotlib.axes.Axes is returned when creating a plot from a dataframe. As such, the dataframe plot can be assigned to a variable, ax, which enables the usage of the associated formatting methods.
  • The default plotting backend for pandas, is matplotlib.
import pandas as pd

# test dataframe
data = {'a': range(20), 'date': pd.bdate_range('2021-01-09', freq='D', periods=20)}
df = pd.DataFrame(data)

# plot the dataframe and assign the returned axes
ax = df.plot(x='date', color='green', ylabel='values', xlabel='date', figsize=(8, 6))

# set various colors
ax.spines['bottom'].set_color('blue')
ax.spines['top'].set_color('red') 
ax.spines['right'].set_color('magenta')
ax.spines['left'].set_color('orange')
ax.xaxis.label.set_color('purple')
ax.yaxis.label.set_color('silver')
ax.tick_params(colors='red', which='both')  # 'both' refers to minor and major axes

enter image description here

Check existence of directory and create if doesn't exist

In terms of general architecture I would recommend the following structure with regard to directory creation. This will cover most potential issues and any other issues with directory creation will be detected by the dir.create call.

mainDir <- "~"
subDir <- "outputDirectory"

if (file.exists(paste(mainDir, subDir, "/", sep = "/", collapse = "/"))) {
    cat("subDir exists in mainDir and is a directory")
} else if (file.exists(paste(mainDir, subDir, sep = "/", collapse = "/"))) {
    cat("subDir exists in mainDir but is a file")
    # you will probably want to handle this separately
} else {
    cat("subDir does not exist in mainDir - creating")
    dir.create(file.path(mainDir, subDir))
}

if (file.exists(paste(mainDir, subDir, "/", sep = "/", collapse = "/"))) {
    # By this point, the directory either existed or has been successfully created
    setwd(file.path(mainDir, subDir))
} else {
    cat("subDir does not exist")
    # Handle this error as appropriate
}

Also be aware that if ~/foo doesn't exist then a call to dir.create('~/foo/bar') will fail unless you specify recursive = TRUE.

ssh-copy-id no identities found error

Actually issues in one of Ubuntu machine is ssh-keygen command was not run properly. I tried running again and navigated into /home/user1/.ssh and able to see id_rsa and id_rsa.pub keys. then tried command ssh-copy-id and it was working fine.

How to have a transparent ImageButton: Android

Try using null for the background ...

android:background="@null"

How to parse SOAP XML?

One of the simplest ways to handle namespace prefixes is simply to strip them from the XML response before passing it through to simplexml such as below:

$your_xml_response = '<Your XML here>';
$clean_xml = str_ireplace(['SOAP-ENV:', 'SOAP:'], '', $your_xml_response);
$xml = simplexml_load_string($clean_xml);

This would return the following:

SimpleXMLElement Object
(
    [Body] => SimpleXMLElement Object
        (
            [PaymentNotification] => SimpleXMLElement Object
                (
                    [payment] => SimpleXMLElement Object
                        (
                            [uniqueReference] => ESDEUR11039872
                            [epacsReference] => 74348dc0-cbf0-df11-b725-001ec9e61285
                            [postingDate] => 2010-11-15T15:19:45
                            [bankCurrency] => EUR
                            [bankAmount] => 1.00
                            [appliedCurrency] => EUR
                            [appliedAmount] => 1.00
                            [countryCode] => ES
                            [bankInformation] => Sean Wood
                            [merchantReference] => ESDEUR11039872
                        )

                )

        )

)

How can I convert a Timestamp into either Date or DateTime object?

java.time

Modern answer: use java.time, the modern Java date and time API, for your date and time work. Back in 2011 it was right to use the Timestamp class, but since JDBC 4.2 it is no longer advised.

For your work we need a time zone and a couple of formatters. We may as well declare them static:

static ZoneId zone = ZoneId.of("America/Marigot");
static DateTimeFormatter dateFormatter = DateTimeFormatter.ofPattern("MM/dd/uuuu");
static DateTimeFormatter timeFormatter = DateTimeFormatter.ofPattern("HH:mm xx");

Now the code could be for example:

    while(resultSet.next()) {
        ZonedDateTime dtStart = resultSet.getObject("dtStart", OffsetDateTime.class)
                 .atZoneSameInstant(zone);

        // I would like to then have the date and time
        // converted into the formats mentioned...
        String dateFormatted = dtStart.format(dateFormatter);
        String timeFormatted = dtStart.format(timeFormatter);
        System.out.format("Date: %s; time: %s%n", dateFormatted, timeFormatted);
    }

Example output (using the time your question was asked):

Date: 09/20/2011; time: 18:13 -0400

In your database timestamp with time zone is recommended for timestamps. If this is what you’ve got, retrieve an OffsetDateTime as I am doing in the code. I am also converting the retrieved value to the user’s time zone before formatting date and time separately. As time zone I supplied America/Marigot as an example, please supply your own. You may also leave out the time zone conversion if you don’t want any, of course.

If the datatype in SQL is a mere timestamp without time zone, retrieve a LocalDateTime instead. For example:

        ZonedDateTime dtStart = resultSet.getObject("dtStart", LocalDateTime.class)
                 .atZone(zone);

No matter the details I trust you to do similarly for dtEnd.

I wasn’t sure what you meant by the xx in HH:MM xx. I just left it in the format pattern string, which yields the UTC offset in hours and minutes without colon.

Link: Oracle tutorial: Date Time explaining how to use java.time.

ssl_error_rx_record_too_long and Apache SSL

In my case I had to change the <VirtualHost *> back to <VirtualHost *:80> (which is the default on Ubuntu). Otherwise, the port 443 wasn't using SSL and was sending plain HTML back to the browser.

You can check whether this is your case quite easily: just connect to your server http://www.example.com:443. If you see plain HTML, your Apache is not using SSL on port 443 at all, most probably due to a VirtualHost misconfiguration.

Cheers!

how to prevent this error : Warning: mysql_fetch_assoc() expects parameter 1 to be resource, boolean given in ... on line 11

If you just want to suppress warnings from a function, you can add an @ sign in front:

<?php @function_that_i_dont_want_to_see_errors_from(parameters); ?>

How to convert datatype:object to float64 in python?

You can try this:

df['2nd'] = pd.to_numeric(df['2nd'].str.replace(',', ''))
df['CTR'] = pd.to_numeric(df['CTR'].str.replace('%', ''))

Using Apache httpclient for https

I put together this test app to reproduce the issue using the HTTP testing framework from the Apache HttpClient package:

ClassLoader cl = HCTest.class.getClassLoader();
URL url = cl.getResource("test.keystore");
KeyStore keystore  = KeyStore.getInstance("jks");
char[] pwd = "nopassword".toCharArray();
keystore.load(url.openStream(), pwd);

TrustManagerFactory tmf = TrustManagerFactory.getInstance(
        TrustManagerFactory.getDefaultAlgorithm());
tmf.init(keystore);
TrustManager[] tm = tmf.getTrustManagers();

KeyManagerFactory kmfactory = KeyManagerFactory.getInstance(
        KeyManagerFactory.getDefaultAlgorithm());
kmfactory.init(keystore, pwd);
KeyManager[] km = kmfactory.getKeyManagers();

SSLContext sslcontext = SSLContext.getInstance("TLS");
sslcontext.init(km, tm, null);

LocalTestServer localServer = new LocalTestServer(sslcontext);
localServer.registerDefaultHandlers();

localServer.start();
try {

    DefaultHttpClient httpclient = new DefaultHttpClient();
    TrustStrategy trustStrategy = new TrustStrategy() {

        public boolean isTrusted(X509Certificate[] chain, String authType) throws CertificateException {
            for (X509Certificate cert: chain) {
                System.err.println(cert);
            }
            return false;
        }

    };

    SSLSocketFactory sslsf = new SSLSocketFactory("TLS", null, null, keystore, null,
            trustStrategy, new AllowAllHostnameVerifier());
    Scheme https = new Scheme("https", 443, sslsf);
    httpclient.getConnectionManager().getSchemeRegistry().register(https);

    InetSocketAddress address = localServer.getServiceAddress();
    HttpHost target1 = new HttpHost(address.getHostName(), address.getPort(), "https");
    HttpGet httpget1 = new HttpGet("/random/100");
    HttpResponse response1 = httpclient.execute(target1, httpget1);
    System.err.println(response1.getStatusLine());
    HttpEntity entity1 = response1.getEntity();
    EntityUtils.consume(entity1);
    HttpHost target2 = new HttpHost("www.verisign.com", 443, "https");
    HttpGet httpget2 = new HttpGet("/");
    HttpResponse response2 = httpclient.execute(target2, httpget2);
    System.err.println(response2.getStatusLine());
    HttpEntity entity2 = response2.getEntity();
    EntityUtils.consume(entity2);
} finally {
    localServer.stop();
}

Even though, Sun's JSSE implementation appears to always read the trust material from the default trust store for some reason, it does not seem to get added to the SSL context and to impact the process of trust verification during the SSL handshake.

Here's the output of the test app. As you can see, the first request succeeds whereas the second fails as the connection to www.verisign.com is rejected as untrusted.

[
[
  Version: V1
  Subject: CN=Simple Test Http Server, OU=Jakarta HttpClient Project, O=Apache Software Foundation, L=Unknown, ST=Unknown, C=Unknown
  Signature Algorithm: SHA1withDSA, OID = 1.2.840.10040.4.3

  Key:  Sun DSA Public Key
    Parameters:DSA
    p:     fd7f5381 1d751229 52df4a9c 2eece4e7 f611b752 3cef4400 c31e3f80 b6512669
    455d4022 51fb593d 8d58fabf c5f5ba30 f6cb9b55 6cd7813b 801d346f f26660b7
    6b9950a5 a49f9fe8 047b1022 c24fbba9 d7feb7c6 1bf83b57 e7c6a8a6 150f04fb
    83f6d3c5 1ec30235 54135a16 9132f675 f3ae2b61 d72aeff2 2203199d d14801c7
    q:     9760508f 15230bcc b292b982 a2eb840b f0581cf5
    g:     f7e1a085 d69b3dde cbbcab5c 36b857b9 7994afbb fa3aea82 f9574c0b 3d078267
    5159578e bad4594f e6710710 8180b449 167123e8 4c281613 b7cf0932 8cc8a6e1
    3c167a8b 547c8d28 e0a3ae1e 2bb3a675 916ea37f 0bfa2135 62f1fb62 7a01243b
    cca4f1be a8519089 a883dfe1 5ae59f06 928b665e 807b5525 64014c3b fecf492a

  y:
    f0cc639f 702fd3b1 03fa8fa6 676c3756 ea505448 23cd1147 fdfa2d7f 662f7c59
    a02ddc1a fd76673e 25210344 cebbc0e7 6250fff1 a814a59f 30ff5c7e c4f186d8
    f0fd346c 29ea270d b054c040 c74a9fc0 55a7020f eacf9f66 a0d86d04 4f4d23de
    7f1d681f 45c4c674 5762b71b 808ded17 05b74baf 8de3c4ab 2ef662e3 053af09e

  Validity: [From: Sat Dec 11 14:48:35 CET 2004,
               To: Tue Dec 09 14:48:35 CET 2014]
  Issuer: CN=Simple Test Http Server, OU=Jakarta HttpClient Project, O=Apache Software Foundation, L=Unknown, ST=Unknown, C=Unknown
  SerialNumber: [    41bafab3]

]
  Algorithm: [SHA1withDSA]
  Signature:
0000: 30 2D 02 15 00 85 BE 6B   D0 91 EF 34 72 05 FF 1A  0-.....k...4r...
0010: DB F6 DE BF 92 53 9B 14   27 02 14 37 8D E8 CB AC  .....S..'..7....
0020: 4E 6C 93 F2 1F 7D 20 A1   2D 6F 80 5F 58 AE 33     Nl.... .-o._X.3

]
HTTP/1.1 200 OK
[
[
  Version: V3
  Subject: CN=www.verisign.com, OU=" Production Security Services", O="VeriSign, Inc.", STREET=487 East Middlefield Road, L=Mountain View, ST=California, OID.2.5.4.17=94043, C=US, SERIALNUMBER=2497886, OID.2.5.4.15="V1.0, Clause 5.(b)", OID.1.3.6.1.4.1.311.60.2.1.2=Delaware, OID.1.3.6.1.4.1.311.60.2.1.3=US
  Signature Algorithm: SHA1withRSA, OID = 1.2.840.113549.1.1.5

  Key:  Sun RSA public key, 2048 bits
  modulus: 20699622354183393041832954221256409980425015218949582822286196083815087464214375375678538878841956356687753084333860738385445545061253653910861690581771234068858443439641948884498053425403458465980515883570440998475638309355278206558031134532548167239684215445939526428677429035048018486881592078320341210422026566944903775926801017506416629554190534665876551381066249522794321313235316733139718653035476771717662585319643139144923795822646805045585537550376512087897918635167815735560529881178122744633480557211052246428978388768010050150525266771462988042507883304193993556759733514505590387262811565107773578140271
  public exponent: 65537
  Validity: [From: Wed May 26 02:00:00 CEST 2010,
               To: Sat May 26 01:59:59 CEST 2012]
  Issuer: CN=VeriSign Class 3 Extended Validation SSL SGC CA, OU=Terms of use at https://www.verisign.com/rpa (c)06, OU=VeriSign Trust Network, O="VeriSign, Inc.", C=US
  SerialNumber: [    53d2bef9 24a7245e 83ca01e4 6caa2477]

Certificate Extensions: 10
[1]: ObjectId: 1.3.6.1.5.5.7.1.1 Criticality=false
AuthorityInfoAccess [
  [accessMethod: 1.3.6.1.5.5.7.48.1
   accessLocation: URIName: http://EVIntl-ocsp.verisign.com, accessMethod: 1.3.6.1.5.5.7.48.2
   accessLocation: URIName: http://EVIntl-aia.verisign.com/EVIntl2006.cer]
]

...

]
Exception in thread "main" javax.net.ssl.SSLPeerUnverifiedException: peer not authenticated
    at com.sun.net.ssl.internal.ssl.SSLSessionImpl.getPeerCertificates(SSLSessionImpl.java:345)
    at org.apache.http.conn.ssl.AbstractVerifier.verify(AbstractVerifier.java:128)
    at org.apache.http.conn.ssl.SSLSocketFactory.createLayeredSocket(SSLSocketFactory.java:446)
...

Powershell's Get-date: How to get Yesterday at 22:00 in a variable?

I saw in at least one other place that people don't realize Date-Time takes in times as well, so I figured I'd share it here since it's really short to do so:

Get-Date # Following the OP's example, let's say it's Friday, March 12, 2010 9:00:00 AM
(Get-Date '22:00').AddDays(-1) # Thursday, March 11, 2010 10:00:00 PM

It's also the shortest way to strip time information and still use other parameters of Get-Date. For instance you can get seconds since 1970 this way (Unix timestamp):

Get-Date '0:00' -u '%s' # 1268352000

Or you can get an ISO 8601 timestamp:

Get-Date '0:00' -f 's' # 2010-03-12T00:00:00

Then again if you reverse the operands, it gives you a little more freedom with formatting with any date object:

'The sortable timestamp: {0:s}Z{1}Vs measly human format: {0:D}' -f (Get-Date '0:00'), "`r`n"
# The sortable timestamp: 2010-03-12T00:00:00Z
# Vs measly human format: Friday, March 12, 2010

However if you wanted to both format a Unix timestamp (via -u aka -UFormat), you'll need to do it separately. Here's an example of that:

'ISO 8601: {0:s}Z{1}Unix: {2}' -f (Get-Date '0:00'), "`r`n", (Get-Date '0:00' -u '%s')
# ISO 8601: 2010-03-12T00:00:00Z
# Unix: 1268352000

Hope this helps!

executing shell command in background from script

For example you have a start program named run.sh to start it working at background do the following command line. ./run.sh &>/dev/null &

An internal error occurred during: "Updating Maven Project". Unsupported IClasspathEntry kind=4

After trying all these procedures it still didn't work for me. What did work was

  1. go into File Explorer and delete the .classpath file under the project's root folder
  2. run Maven update within Eclipse, and check Force update of Snapshots/Releases

Our current work required integrating a number of disparate projects so unfortunately use of SNAPSHOTs in a production environment were required (taboo in Maven circles)!

Extract digits from a string in Java

Use regular expression to match your requirement.

String num,num1,num2;
String str = "123-456-789";
String regex ="(\\d+)";
Matcher matcher = Pattern.compile( regex ).matcher( str);
while (matcher.find( ))
{
num = matcher.group();     
System.out.print(num);                 
}

How to squash all git commits into one?

If all you want to do is squash all of your commits down to the root commit, then while

git rebase --interactive --root

can work, it's impractical for a large number of commits (for example, hundreds of commits), because the rebase operation will probably run very slowly to generate the interactive rebase editor commit list, as well as run the rebase itself.

Here are two quicker and more efficient solutions when you're squashing a large number of commits:

Alternative solution #1: orphan branches

You can simply create a new orphan branch at the tip (i.e. the most recent commit) of your current branch. This orphan branch forms the initial root commit of an entirely new and separate commit history tree, which is effectively equivalent to squashing all of your commits:

git checkout --orphan new-master master
git commit -m "Enter commit message for your new initial commit"

# Overwrite the old master branch reference with the new one
git branch -M new-master master

Documentation:

Alternative solution #2: soft reset

Another efficient solution is to simply use a mixed or soft reset to the root commit <root>:

git branch beforeReset

git reset --soft <root>
git commit --amend

# Verify that the new amended root is no different
# from the previous branch state
git diff beforeReset

Documentation:

Form Submit jQuery does not work

if there is one error in the the submit function,the submit function will be execute. in other sentences prevent default(or return false) does not work when one error exist in submit function.

from jquery $.ajax to angular $http

You may use this :

Download "angular-post-fix": "^0.1.0"

Then add 'httpPostFix' to your dependencies while declaring the angular module.

Ref : https://github.com/PabloDeGrote/angular-httppostfix

Assets file project.assets.json not found. Run a NuGet package restore

In visual studio 2017 please do following steps:

1) select Tool=>Options=>NuGet Package Manager=> Package Sources then uncheck Microsoft Visual Studio Offline Packages Option. enter image description here

2) now open Tool=>NuGet Package Maneger=>Package Manager Console. 3) execute command in PM>dotnet restore.

Hope its working...

Serializing class instance to JSON

You can specify the default named parameter in the json.dumps() function:

json.dumps(obj, default=lambda x: x.__dict__)

Explanation:

Form the docs (2.7, 3.6):

``default(obj)`` is a function that should return a serializable version
of obj or raise TypeError. The default simply raises TypeError.

(Works on Python 2.7 and Python 3.x)

Note: In this case you need instance variables and not class variables, as the example in the question tries to do. (I am assuming the asker meant class instance to be an object of a class)

I learned this first from @phihag's answer here. Found it to be the simplest and cleanest way to do the job.

if-else statement inside jsx: ReactJS

I find this way is the nicest:

{this.state.yourVariable === 'news' && <Text>{data}<Text/>}

How can I escape a single quote?

use javascript inbuild functions escape and unescape

for example

var escapedData = escape("hel'lo");   
output = "%27hel%27lo%27" which can be used in the attribute.

again to read the value from the attr

var unescapedData = unescape("%27hel%27lo%27")
output = "'hel'lo'"

This will be helpful if you have huge json stringify data to be used in the attribute

Add new element to an existing object

Use this:

myFunction.bookName = 'mybook';
myFunction.bookdesc = 'new';

Or, if you are using jQuery:

$(myFunction).extend({
    bookName:'mybook',
    bookdesc: 'new'
});

The push method is wrong because it belongs to the Array.prototype object.

To create a named object, try this:

var myObj = function(){
    this.property = 'foo';
    this.bar = function(){
    }
}
myObj.prototype.objProp = true;
var newObj = new myObj();

Calculate mean and standard deviation from a vector of samples in C++ using Boost

It seems the following elegant recursive solution has not been mentioned, although it has been around for a long time. Referring to Knuth's Art of Computer Programming,

mean_1 = x_1, variance_1 = 0;            //initial conditions; edge case;

//for k >= 2, 
mean_k     = mean_k-1 + (x_k - mean_k-1) / k;
variance_k = variance_k-1 + (x_k - mean_k-1) * (x_k - mean_k);

then for a list of n>=2 values, the estimate of the standard deviation is:

stddev = std::sqrt(variance_n / (n-1)). 

Hope this helps!

How to retrieve JSON Data Array from ExtJS Store

A better (IMO) one-line approach, works on ExtJS 4, not sure about 3:

store.proxy.reader.jsonData

How to append elements into a dictionary in Swift?

If your dictionary is Int to String you can do simply:

dict[3] = "efg"

If you mean adding elements to the value of the dictionary a possible solution:

var dict = Dictionary<String, Array<Int>>()

dict["key"]! += [1]
dict["key"]!.append(1)
dict["key"]?.append(1)

Android requires compiler compliance level 5.0 or 6.0. Found '1.7' instead. Please use Android Tools > Fix Project Properties

In my case a switch from openjdk7 to openjdk6 helped. Afterwards I changed the compliance level to 1.6 and all compiled fine.

How to implement class constants?

For me none of earlier answer works. I did need to convert my static class to enum. Like this:

export enum MyConstants {
  MyFirstConstant = 'MyFirstConstant',
  MySecondConstant = 'MySecondConstant'
}

Then in my component I add new property as suggested in other answers

export class MyComponent {
public MY_CONTANTS = MyConstans;
constructor() { }
}

Then in my component's template I use it this way

<div [myDirective]="MY_CONTANTS.MyFirstConstant"> </div>

EDIT: Sorry. My problem was different than OP's. I still leave this here if someelse have same problem than I.

How do I change the figure size for a seaborn plot?

The top answers by Paul H and J. Li do not work for all types of seaborn figures. For the FacetGrid type (for instance sns.lmplot()), use the size and aspect parameter.

Size changes both the height and width, maintaining the aspect ratio.

Aspect only changes the width, keeping the height constant.

You can always get your desired size by playing with these two parameters.

Credit: https://stackoverflow.com/a/28765059/3901029

Equivalent of Oracle's RowID in SQL Server

If you want to permanently number the rows in the table, Please don't use the RID solution for SQL Server. It will perform worse than Access on an old 386. For SQL Server simply create an IDENTITY column, and use that column as a clustered primary key. This will place a permanent, fast Integer B-Tree on the table, and more importantly every non-clustered index will use it to locate rows. If you try to develop in SQL Server as if it's Oracle you'll create a poorly performing database. You need to optimize for the engine, not pretend it's a different engine.

also, please don't use the NewID() to populate the Primary Key with GUIDs, you'll kill insert performance. If you must use GUIDs use NewSequentialID() as the column default. But INT will still be faster.

If on the other hand, you simply want to number the rows that result from a query, use the RowNumber Over() function as one of the query columns.

Why do I need to do `--set-upstream` all the time?

You can simply

git checkout -b my-branch origin/whatever

in the first place. If you set branch.autosetupmerge or branch.autosetuprebase (my favorite) to always (default is true), my-branch will automatically track origin/whatever.

See git help config.

How to update/modify an XML file in python?

To make this process more robust, you could consider using the SAX parser (that way you don't have to hold the whole file in memory), read & write till the end of tree and then start appending.

How to escape % in String.Format?

To escape %, you will need to double it up: %%.

How to combine multiple inline style objects?

To Expand on what @PythonIsGreat said, I create a global function that will do it for me:

var css = function(){
    var args = $.merge([true, {}], Array.prototype.splice.call(arguments, 0));
    return $.extend.apply(null, args);
}

This deeply extends the objects into a new object and allows for a variable number of objects as parameters. This allows you to do something like this:

return(
<div style={css(styles.base, styles.first, styles.second,...)} ></div>
);

var styles = {
  base:{
    //whatever
  },
  first:{
    //whatever
  },
  second:{
    //whatever
  }
}

How to install Anaconda on RaspBerry Pi 3 Model B

Installing Miniconda on Raspberry Pi and adding Python 3.5 / 3.6

Skip the first section if you have already installed Miniconda successfully.

Installation of Miniconda on Raspberry Pi

wget http://repo.continuum.io/miniconda/Miniconda3-latest-Linux-armv7l.sh
sudo md5sum Miniconda3-latest-Linux-armv7l.sh
sudo /bin/bash Miniconda3-latest-Linux-armv7l.sh

Accept the license agreement with yes

When asked, change the install location: /home/pi/miniconda3

Do you wish the installer to prepend the Miniconda3 install location to PATH in your /root/.bashrc ? yes

Now add the install path to the PATH variable:

sudo nano /home/pi/.bashrc

Go to the end of the file .bashrc and add the following line:

export PATH="/home/pi/miniconda3/bin:$PATH"

Save the file and exit.

To test if the installation was successful, open a new terminal and enter

conda

If you see a list with commands you are ready to go.

But how can you use Python versions greater than 3.4 ?


Adding Python 3.5 / 3.6 to Miniconda on Raspberry Pi

After the installation of Miniconda I could not yet install Python versions higher than Python 3.4, but i needed Python 3.5. Here is the solution which worked for me on my Raspberry Pi 4:

First i added the Berryconda package manager by jjhelmus (kind of an up-to-date version of the armv7l version of Miniconda):

conda config --add channels rpi

Only now I was able to install Python 3.5 or 3.6 without the need for compiling it myself:

conda install python=3.5
conda install python=3.6

Afterwards I was able to create environments with the added Python version, e.g. with Python 3.5:

conda create --name py35 python=3.5

The new environment "py35" can now be activated:

source activate py35

Using Python 3.7 on Raspberry Pi

Currently Jonathan Helmus, who is the developer of berryconda, is working on adding Python 3.7 support, if you want to see if there is an update or if you want to support him, have a look at this pull request. (update 20200623) berryconda is now inactive, This project is no longer active, no recipe will be updated and no packages will be added to the rpi channel. If you need to run Python 3.7 on your Pi right now, you can do so without Miniconda. Check if you are running the latest version of Raspbian OS called Buster. Buster ships with Python 3.7 preinstalled (source), so simply run your program with the following command:

Python3.7 app-that-needs-python37.py

I hope this solution will work for you too!

SQL Server: the maximum number of rows in table

I don't know MSSQL specifically, but 36 million rows is not large to an enterprise database - working with mainframe databases, 100,000 rows sounds like a configuration table to me :-).

While I'm not a big fan of some of Microsoft's software, this isn't Access we're talking about here: I assume they can handle pretty substantial database sizes with their enterprise DBMS.

I suspect days may have been too fine a resolution to divide it up, if indeed it needs dividing at all.

Pass PDO prepared statement to variables

Instead of using ->bindParam() you can pass the data only at the time of ->execute():

$data = [   ':item_name' => $_POST['item_name'],   ':item_type' => $_POST['item_type'],   ':item_price' => $_POST['item_price'],   ':item_description' => $_POST['item_description'],   ':image_location' => 'images/'.$_FILES['file']['name'],   ':status' => 0,   ':id' => 0, ];  $stmt->execute($data); 

In this way you would know exactly what values are going to be sent.

Tensorflow: Using Adam optimizer

You need to call tf.global_variables_initializer() on you session, like

init = tf.global_variables_initializer()
sess.run(init)

Full example is available in this great tutorial https://www.tensorflow.org/get_started/mnist/mechanics

SQL Logic Operator Precedence: And and Or

And has precedence over Or, so, even if a <=> a1 Or a2

Where a And b 

is not the same as

Where a1 Or a2 And b,

because that would be Executed as

Where a1 Or (a2 And b)

and what you want, to make them the same, is the following (using parentheses to override rules of precedence):

 Where (a1 Or a2) And b

Here's an example to illustrate:

Declare @x tinyInt = 1
Declare @y tinyInt = 0
Declare @z tinyInt = 0

Select Case When @x=1 OR @y=1 And @z=1 Then 'T' Else 'F' End -- outputs T
Select Case When (@x=1 OR @y=1) And @z=1 Then 'T' Else 'F' End -- outputs F

For those who like to consult references (in alphabetic order):

How to rename with prefix/suffix?

You could use the rename(1) command:

rename 's/(.*)$/new.$1/' original.filename

Edit: If rename isn't available and you have to rename more than one file, shell scripting can really be short and simple for this. For example, to rename all *.jpg to prefix_*.jpg in the current directory:

for filename in *.jpg; do mv "$filename" "prefix_$filename"; done;

JavaScript - Get Browser Height

You can use the window.innerHeight

INSERT INTO from two different server database

USE [mydb1]

SELECT *
INTO mytable1
FROM OPENDATASOURCE (
        'SQLNCLI'
        ,'Data Source=XXX.XX.XX.XXX;Initial Catalog=mydb2;User ID=XXX;Password=XXXX'
        ).[mydb2].dbo.mytable2
    /*  steps - 
            1-  [mydb1] means our opend connection database 
            2-  mytable1 means create copy table in mydb1 database where we want insert record
            3-  XXX.XX.XX.XXX - another server name.
            4-  mydb2 another server database.
            5-  write User id and Password of another server credential
            6-  mytable2 is another server table where u fetch record from it. */

Add CSS class to a div in code behind

Button1.CssClass += " newClass";

This will not erase your original classes for that control. Try this, it should work.

SeekBar and media player in android

To create a 'connection' between SeekBar and MediaPlayer you need first to get your current recording max duration and set it to your seek bar.

mSeekBar.setMax(mFileDuration/1000); // where mFileDuration is mMediaPlayer.getDuration();

After you initialise your MediaPlayer and for example press play button, you should create handler and post runnable so you can update your SeekBar (in the UI thread itself) with the current position of your MediaPlayer like this :

private Handler mHandler = new Handler();
//Make sure you update Seekbar on UI thread
MainActivity.this.runOnUiThread(new Runnable() {

    @Override
    public void run() {
        if(mMediaPlayer != null){
            int mCurrentPosition = mMediaPlayer.getCurrentPosition() / 1000;
            mSeekBar.setProgress(mCurrentPosition);
        }
        mHandler.postDelayed(this, 1000);
    }
});

and update that value every second.

If you need to update the MediaPlayer's position while user drag your SeekBar you should add OnSeekBarChangeListener to your SeekBar and do it there :

        mSeekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {

        @Override
        public void onStopTrackingTouch(SeekBar seekBar) {

        }

        @Override
        public void onStartTrackingTouch(SeekBar seekBar) {

        }

            @Override
            public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {                
                if(mMediaPlayer != null && fromUser){
                    mMediaPlayer.seekTo(progress * 1000);
                }
            }
    });

And that should do the trick! : )

EDIT: One thing which I've noticed in your code, don't do :

public MainActivity() {
    mFileName = Environment.getExternalStorageDirectory().getAbsolutePath();
    mFileName += "/audiorecordtest.3gp";
}

make all initialisations in your onCreate(); , do not create constructors of your Activity.

Easiest way to convert month name to month number in JS ? (Jan = 01)

Here is a simple one liner function

//ECHMA5
function GetMonth(anyDate) { 
   return 'Jan,Feb,Mar,Apr,May,Jun,Jul,Aug,Sep,Oct,Nov,Dec'.split(',')[anyDate.getMonth()];
 }
//
// ECMA6
var GetMonth = (anyDate) => 'Jan,Feb,Mar,Apr,May,Jun,Jul,Aug,Sep,Oct,Nov,Dec'.split(',')[anyDate.getMonth()];

Converting an array to a function arguments list

@bryc - yes, you could do it like this:

Element.prototype.setAttribute.apply(document.body,["foo","bar"])

But that seems like a lot of work and obfuscation compared to:

document.body.setAttribute("foo","bar")

How to override toString() properly in Java?

Well actually you will need to return something like this because toString has to return a string

public String toString() {
 return "Name :" + this.name + "whatever :" + this.whatever + "";
}

and you actually do something wrong in the constructer you set the variable the user set to the name while you need to do the opposite. What you shouldn't do

n = this.name

What you should do

this.name = n

Hopes this helps thanks

Best way to check if object exists in Entity Framework?

Best way to do it

Regardless of what your object is and for what table in the database the only thing you need to have is the primary key in the object.

C# Code

var dbValue = EntityObject.Entry(obj).GetDatabaseValues();
if (dbValue == null)
{
   Don't exist
}

VB.NET Code

Dim dbValue = EntityObject.Entry(obj).GetDatabaseValues()
If dbValue Is Nothing Then
   Don't exist
End If

foreach for JSON array , syntax

You can use the .forEach() method of JavaScript for looping through JSON.

_x000D_
_x000D_
var datesBooking = [_x000D_
    {"date": "04\/24\/2018"},_x000D_
      {"date": "04\/25\/2018"}_x000D_
    ];_x000D_
    _x000D_
    datesBooking.forEach(function(data, index) {_x000D_
      console.log(data);_x000D_
    });
_x000D_
_x000D_
_x000D_

Stratified Train/Test-split in scikit-learn

Here's an example for continuous/regression data (until this issue on GitHub is resolved).

min = np.amin(y)
max = np.amax(y)

# 5 bins may be too few for larger datasets.
bins     = np.linspace(start=min, stop=max, num=5)
y_binned = np.digitize(y, bins, right=True)

X_train, X_test, y_train, y_test = train_test_split(
    X, 
    y, 
    stratify=y_binned
)
  • Where start is min and stop is max of your continuous target.
  • If you don't set right=True then it will more or less make your max value a separate bin and your split will always fail because too few samples will be in that extra bin.

PHP XML Extension: Not installed

You're close

sudo apt-get install php-xml

Then you need to restart apache so it takes effect

sudo service apache2 restart

load external css file in body tag

No, it is not okay to put a link element in the body tag. See the specification (links to the HTML4.01 specs, but I believe it is true for all versions of HTML):

“This element defines a link. Unlike A, it may only appear in the HEAD section of a document, although it may appear any number of times.”

Is there any JSON Web Token (JWT) example in C#?

Here is the list of classes and functions:

open System
open System.Collections.Generic
open System.Linq
open System.Threading.Tasks
open Microsoft.AspNetCore.Mvc
open Microsoft.Extensions.Logging
open Microsoft.AspNetCore.Authorization
open Microsoft.AspNetCore.Authentication
open Microsoft.AspNetCore.Authentication.JwtBearer
open Microsoft.IdentityModel.Tokens
open System.IdentityModel.Tokens
open System.IdentityModel.Tokens.Jwt
open Microsoft.IdentityModel.JsonWebTokens
open System.Text
open Newtonsoft.Json
open System.Security.Claims
    let theKey = "VerySecretKeyVerySecretKeyVerySecretKey"
    let securityKey = SymmetricSecurityKey(Encoding.UTF8.GetBytes(theKey))
    let credentials = SigningCredentials(securityKey, SecurityAlgorithms.RsaSsaPssSha256)
    let expires = DateTime.UtcNow.AddMinutes(123.0) |> Nullable
    let token = JwtSecurityToken(
                    "lahoda-pro-issuer", 
                    "lahoda-pro-audience",
                    claims = null,
                    expires =  expires,
                    signingCredentials = credentials
        )

    let tokenString = JwtSecurityTokenHandler().WriteToken(token)

Jquery Smooth Scroll To DIV - Using ID value from Link

You can do this:

$('.searchbychar').click(function () {
    var divID = '#' + this.id;
    $('html, body').animate({
        scrollTop: $(divID).offset().top
    }, 2000);
});

F.Y.I.

  • You need to prefix a class name with a . (dot) like in your first line of code.
  • $( 'searchbychar' ).click(function() {
  • Also, your code $('.searchbychar').attr('id') will return a string ID not a jQuery object. Hence, you can not apply .offset() method to it.

HtmlSpecialChars equivalent in Javascript?

Underscore.js provides a function for this:

_.escape(string)

Escapes a string for insertion into HTML, replacing &, <, >, ", and ' characters.

http://underscorejs.org/#escape

It's not a built-in Javascript function, but if you are already using Underscore it is a better alternative than writing your own function if your strings to convert are not too large.

How to remove border of drop down list : CSS

This solution seems not working for me.

select {
    border: 0px;
    outline: 0px;
}

But you may set select border to the background color of the container and it will work.

Making a POST call instead of GET using urllib2

This may have been answered before: Python URLLib / URLLib2 POST.

Your server is likely performing a 302 redirect from http://myserver/post_service to http://myserver/post_service/. When the 302 redirect is performed, the request changes from POST to GET (see Issue 1401). Try changing url to http://myserver/post_service/.

JavaScript editor within Eclipse

Disclaimer, I work at Aptana. I would point out there are some nice features for JS that you might not get so easily elsewhere. One is plugin-level integration of JS libraries that provide CodeAssist, samples, snippets and easy inclusion of the libraries files into your project; we provide the plugins for many of the more commonly used libraries, including YUI, jQuery, Prototype, dojo and EXT JS.

Second, we have a server-side JavaScript engine called Jaxer that not only lets you run any of your JS code on the server but adds file, database and networking functionality so that you don't have to use a scripting language but can write the entire app in JS.

How to remove old and unused Docker images

@VonC already gave a very nice answer, but for completeness here is a little script I have been using---and which also nukes any errand Docker processes should you have some:

#!/bin/bash

imgs=$(docker images | awk '/<none>/ { print $3 }')
if [ "${imgs}" != "" ]; then
   echo docker rmi ${imgs}
   docker rmi ${imgs}
else
   echo "No images to remove"
fi

procs=$(docker ps -a -q --no-trunc)
if [ "${procs}" != "" ]; then
   echo docker rm ${procs}
   docker rm ${procs}
else
   echo "No processes to purge"
fi

Google drive limit number of download

This limit is indeed not specified, however their TOS mentions that: "FOR EXAMPLE, WE DON’T MAKE ANY COMMITMENTS ABOUT THE CONTENT WITHIN THE SERVICES, THE SPECIFIC FUNCTIONS OF THE SERVICES, OR THEIR RELIABILITY, AVAILABILITY, OR ABILITY TO MEET YOUR NEEDS. WE PROVIDE THE SERVICES “AS IS”. "

This means to me that the download limit is calculated based on a set of factors that describe the user and is subject to change from one to another.

Maybe using the TOR network may help you do your job.

C# Double - ToString() formatting with two decimal places but no rounding

I know this is a old thread but I've just had to do this. While the other approaches here work, I wanted an easy way to be able to affect a lot of calls to string.format. So adding the Math.Truncate to all the calls to wasn't really a good option. Also as some of the formatting is stored in a database, it made it even worse.

Thus, I made a custom format provider which would allow me to add truncation to the formatting string, eg:

string.format(new FormatProvider(), "{0:T}", 1.1299); // 1.12
string.format(new FormatProvider(), "{0:T(3)", 1.12399); // 1.123
string.format(new FormatProvider(), "{0:T(1)0,000.0", 1000.9999); // 1,000.9

The implementation is pretty simple and is easily extendible to other requirements.

public class FormatProvider : IFormatProvider, ICustomFormatter
{
    public object GetFormat(Type formatType)
    {
        if (formatType == typeof (ICustomFormatter))
        {
            return this;
        }
        return null;
    }

    public string Format(string format, object arg, IFormatProvider formatProvider)
    {
        if (arg == null || arg.GetType() != typeof (double))
        {
            try
            {
                return HandleOtherFormats(format, arg);
            }
            catch (FormatException e)
            {
                throw new FormatException(string.Format("The format of '{0}' is invalid.", format));
            }
        }

        if (format.StartsWith("T"))
        {
            int dp = 2;
            int idx = 1;
            if (format.Length > 1)
            {
                if (format[1] == '(')
                {
                    int closeIdx = format.IndexOf(')');
                    if (closeIdx > 0)
                    {
                        if (int.TryParse(format.Substring(2, closeIdx - 2), out dp))
                        {
                            idx = closeIdx + 1;
                        }
                    }
                    else
                    {
                        throw new FormatException(string.Format("The format of '{0}' is invalid.", format));
                    }
                }
            }
            double mult = Math.Pow(10, dp);
            arg = Math.Truncate((double)arg * mult) / mult;
            format = format.Substring(idx);
        }

        try
        {
            return HandleOtherFormats(format, arg);
        }
        catch (FormatException e)
        {
            throw new FormatException(string.Format("The format of '{0}' is invalid.", format));
        }
    }

    private string HandleOtherFormats(string format, object arg)
    {
        if (arg is IFormattable)
        {
            return ((IFormattable) arg).ToString(format, CultureInfo.CurrentCulture);
        }
        return arg != null ? arg.ToString() : String.Empty;
    }
}

Visualizing decision tree in scikit-learn

sklearn.tree.export_graphviz doesn't return anything, and so by default returns None.

By doing dotfile = tree.export_graphviz(...) you overwrite your open file object, which had been previously assigned to dotfile, so you get an error when you try to close the file (as it's now None).

To fix it change your code to

...
dotfile = open("D:/dtree2.dot", 'w')
tree.export_graphviz(dtree, out_file = dotfile, feature_names = X.columns)
dotfile.close()
...

Retrieving a List from a java.util.stream.Stream in Java 8

If you have an array of primitives, you can use the primitive collections available in Eclipse Collections.

LongList sourceLongList = LongLists.mutable.of(1L, 10L, 50L, 80L, 100L, 120L, 133L, 333L);
LongList targetLongList = sourceLongList.select(l -> l > 100);

If you can't change the sourceLongList from List:

List<Long> sourceLongList = Arrays.asList(1L, 10L, 50L, 80L, 100L, 120L, 133L, 333L);
List<Long> targetLongList = 
    ListAdapter.adapt(sourceLongList).select(l -> l > 100, new ArrayList<>());

If you want to use LongStream:

long[] sourceLongs = new long[]{1L, 10L, 50L, 80L, 100L, 120L, 133L, 333L};
LongList targetList = 
    LongStream.of(sourceLongs)
    .filter(l -> l > 100)
    .collect(LongArrayList::new, LongArrayList::add, LongArrayList::addAll);

Note: I am a contributor to Eclipse Collections.

How can I tell when HttpClient has timed out?

You need to await the GetAsync method. It will then throw a TaskCanceledException if it has timed out. Additionally, GetStringAsync and GetStreamAsync internally handle timeout, so they will NEVER throw.

string baseAddress = "http://localhost:8080/";
var client = new HttpClient() 
{ 
    BaseAddress = new Uri(baseAddress), 
    Timeout = TimeSpan.FromMilliseconds(1) 
};
try
{
    var s = await client.GetAsync();
}
catch(Exception e)
{
    Console.WriteLine(e.Message);
    Console.WriteLine(e.InnerException.Message);
}

How do you use $sce.trustAsHtml(string) to replicate ng-bind-html-unsafe in Angular 1.2+

Filter

app.filter('unsafe', function($sce) { return $sce.trustAsHtml; });

Usage

<ANY ng-bind-html="value | unsafe"></ANY>

What is a callback in java

In Java, callback methods are mainly used to address the "Observer Pattern", which is closely related to "Asynchronous Programming".

Although callbacks are also used to simulate passing methods as a parameter, like what is done in functional programming languages.

C# function to return array

return Labels; should do the trick!

public static ArtworkData[] GetDataRecords(int UsersID)
{
    ArtworkData[] Labels;
    Labels = new ArtworkData[3];

    return Labels;
}

npm not working after clearing cache

try this one npm cache clean --force after that run npm cache verify

Default SecurityProtocol in .NET 4.5

If you can use .NET 4.7.1 or newer, it will use TLS 1.2 as the minimum protocol based on the operating system capabilities. Per Microsoft recommendation :

To ensure .NET Framework applications remain secure, the TLS version should not be hardcoded. .NET Framework applications should use the TLS version the operating system (OS) supports.

Add Marker function with Google Maps API

Below code works for me:

<script src="http://maps.googleapis.com/maps/api/js"></script>
<script>
    var myCenter = new google.maps.LatLng(51.528308, -0.3817765);

    function initialize() {
           var mapProp = {
            center:myCenter,
            zoom:15,
            mapTypeId:google.maps.MapTypeId.ROADMAP
        };
        var map = new google.maps.Map(document.getElementById("googleMap"), mapProp); 

        var marker = new google.maps.Marker({
            position: myCenter,
            icon: {
                url: '/images/marker.png',
                size: new google.maps.Size(70, 86), //marker image size
                origin: new google.maps.Point(0, 0), // marker origin
                anchor: new google.maps.Point(35, 86) // X-axis value (35, half of marker width) and 86 is Y-axis value (height of the marker).
            }
        });

        marker.setMap(map);

        }
        google.maps.event.addDomListener(window, 'load', initialize);

</script>
<body>
<div id="googleMap" style="width:500px;height:380px;"></div>
</body>

Reference link

Getting the source of a specific image element with jQuery

$('img.conversation_img[alt="example"]')
    .each(function(){
         alert($(this).attr('src'))
    });

This will display src attributes of all images of class 'conversation_img' with alt='example'

Simple way to find if two different lists contain exactly the same elements?

Check both lists are not nulls. If their sizes are different, then these lists are not equal. Build maps consisting of the lists' elements as keys and their repeats as values and compare the maps.

Assumptions, if both lists are nulls, I consider them equal.

private boolean compareLists(List<?> l1, List<?> l2) {
    if (l1 == null && l2 == null) {
        return true;
    } else if (l1 == null || l2 == null) {
        return false;
    }

    if (l1.size() != l2.size()) {
        return false;
    }

    Map<?, Integer> m1 = toMap(l1);
    Map<?, Integer> m2 = toMap(l2);

    return m1.equals(m2);
}

private Map<Object, Integer> toMap(List<?> list) {
    //Effective size, not to resize in the future.
    int mapSize = (int) (list.size() / 0.75 + 1);
    Map<Object, Integer> map = new HashMap<>(mapSize);

    for (Object o : list) {
        Integer count = map.get(o);
        if (count == null) {
            map.put(o, 1);
        } else {
            map.put(o, ++count);
        }
    }

    System.out.println(map);
    return map;
}

Please, note, method equals should be properly defined for these objects. https://stackoverflow.com/a/24814634/4587961

How to call javascript function from asp.net button click event

If you don't need to initiate a post back when you press this button, then making the overhead of a server control isn't necesary.

<input id="addButton" type="button" value="Add" />

<script type="text/javascript" language="javascript">
     $(document).ready(function()
     {
         $('#addButton').click(function() 
         { 
             showDialog('#addPerson'); 
         });
     });
</script>

If you still need to be able to do a post back, you can conditionally stop the rest of the button actions with a little different code:

<asp:Button ID="buttonAdd" runat="server" Text="Add" />

<script type="text/javascript" language="javascript">
     $(document).ready(function()
     {
         $('#<%= buttonAdd.ClientID %>').click(function(e) 
         { 
             showDialog('#addPerson');

             if(/*Some Condition Is Not Met*/) 
                return false;
         });
     });
</script>

How do I make entire div a link?

Wrapping a <a> around won't work (unless you set the <div> to display:inline-block; or display:block; to the <a>) because the div is s a block-level element and the <a> is not.

<a href="http://www.example.com" style="display:block;">
   <div>
       content
   </div>
</a>

<a href="http://www.example.com">
   <div style="display:inline-block;">
       content
   </div>
</a>

<a href="http://www.example.com">
   <span>
       content
   </span >
</a>

<a href="http://www.example.com">
   content
</a>

But maybe you should skip the <div> and choose a <span> instead, or just the plain <a>. And if you really want to make the div clickable, you could attach a javascript redirect with a onclick handler, somethign like:

document.getElementById("myId").setAttribute('onclick', 'location.href = "url"'); 

but I would recommend against that.

How to scroll to an element?

Just a heads up, I couldn't get these solutions to work on Material UI components. Looks like they don't have the current property.

I just added an empty div amongst my components and set the ref prop on that.

MongoDB Data directory /data/db not found

MongoDB needs data directory to store data. Default path is /data/db

When you start MongoDB engine, it searches this directory which is missing in your case. Solution is create this directory and assign rwx permission to user.

If you want to change the path of your data directory then you should specify it while starting mongod server like,

mongod --dbpath /data/<path> --port <port no> 

This should help you start your mongod server with custom path and port.

Spring Boot REST API - request timeout?

I feel like none of the answers really solve the issue. I think you need to tell the embedded server of Spring Boot what should be the maximum time to process a request. How exactly we do that is dependent on the type of the embedded server used.

In case of Undertow, one can do this:

@Component
class WebServerCustomizer : WebServerFactoryCustomizer<UndertowServletWebServerFactory> {
    override fun customize(factory: UndertowServletWebServerFactory) {
        factory.addBuilderCustomizers(UndertowBuilderCustomizer {
            it.setSocketOption(Options.READ_TIMEOUT, 5000)
            it.setSocketOption(Options.WRITE_TIMEOUT, 25000)
        })
    }
}

Spring Boot official doc: https://docs.spring.io/spring-boot/docs/2.2.0.RELEASE/reference/html/howto.html#howto-configure-webserver

Dynamic LINQ OrderBy on IEnumerable<T> / IQueryable<T>

You can convert the IEnumerable to IQueryable.

items = items.AsQueryable().OrderBy("Name ASC");

How to plot a function curve in R

Here is a lattice version:

library(lattice)
eq<-function(x) {x*x}
X<-1:1000
xyplot(eq(X)~X,type="l")

Lattice output

What does 'const static' mean in C and C++?

It has uses in both C and C++.

As you guessed, the static part limits its scope to that compilation unit. It also provides for static initialization. const just tells the compiler to not let anybody modify it. This variable is either put in the data or bss segment depending on the architecture, and might be in memory marked read-only.

All that is how C treats these variables (or how C++ treats namespace variables). In C++, a member marked static is shared by all instances of a given class. Whether it's private or not doesn't affect the fact that one variable is shared by multiple instances. Having const on there will warn you if any code would try to modify that.

If it was strictly private, then each instance of the class would get its own version (optimizer notwithstanding).

How to open/run .jar file (double-click not working)?

You may have several JDKs installed in your PC. Some older JDK installers also copy some java files such as java.exe, javaw.exe into C:\Windows\System32 folder.

I had a similar issue, and searched the internet for a solution and none of the suggestions didn’t open by double clicking the .jar file.

In my case the reason is I have multiple JDK & JRE versions installed on my computer. Since I am a software developer working with several different versions for different clients I need to use multiple JDKs in my PC (Windows 10 Pro). So I do not want to change the system variables (i.e. JAVA_HOME, JRE_HOME or PATH), instead I use command prompt to run java in user process whenever I wanted to use a different version.

When installing JDK it registers the .jar file association with latest version we installed in the PC. If you right click on the .jar icon and select properties, it will show that file opens with “Java(TM) Platform SE Binary”. If we look at the registry key: HKEY_CLASSES_ROOT\jarfile\shell\open\command, it will point to latest JDK version.

It is not a good idea (sometimes annoying) to change the registry key every time I want to run an app build from a different version.

So in my situation it is impossible to just double click the .jar file to execute it. But instead I found a work around solution myself.

Scenario:

Multiple JDKs (1.7, 1.8, 9.0, 10.0, 11.0, and 12.0)are installed in the PC, so the latest installed was 12.0.

Problem

Want to double click an executable .jar developed using JDK 1.8 and didn’t work

This is my work around solution:

  1. Create a shortcut for the .jar file that you want to open.

  2. Right click the shortcut icon and select properties -> Shortcut tab

  3. Change the text in the target (for example "D:\Dev\JavaApp1.8.jar") To

    "C:\Program Files\Java\jdk1.8.0\bin\javaw.exe" -jar "D:\Dev\JavaApp1.8.jar"

  4. Then click ok Double click the shortcut.

It should now open the app.

Is it possible to send a variable number of arguments to a JavaScript function?

Update: Since ES6, you can simply use the spread syntax when calling the function:

func(...arr);

Since ES6 also if you expect to treat your arguments as an array, you can also use the spread syntax in the parameter list, for example:

function func(...args) {
  args.forEach(arg => console.log(arg))
}

const values = ['a', 'b', 'c']
func(...values)
func(1, 2, 3)

And you can combine it with normal parameters, for example if you want to receive the first two arguments separately and the rest as an array:

function func(first, second, ...theRest) {
  //...
}

And maybe is useful to you, that you can know how many arguments a function expects:

var test = function (one, two, three) {}; 
test.length == 3;

But anyway you can pass an arbitrary number of arguments...

The spread syntax is shorter and "sweeter" than apply and if you don't need to set the this value in the function call, this is the way to go.

Here is an apply example, which was the former way to do it:

var arr = ['a','b','c'];

function func() {
  console.log(this); // 'test'
  console.log(arguments.length); // 3

  for(var i = 0; i < arguments.length; i++) {
    console.log(arguments[i]);
  }

};

func.apply('test', arr);

Nowadays I only recommend using apply only if you need to pass an arbitrary number of arguments from an array and set the this value. apply takes is the this value as the first arguments, which will be used on the function invocation, if we use null in non-strict code, the this keyword will refer to the Global object (window) inside func, in strict mode, when explicitly using 'use strict' or in ES modules, null will be used.

Also note that the arguments object is not really an Array, you can convert it by:

var argsArray = Array.prototype.slice.call(arguments);

And in ES6:

const argsArray = [...arguments] // or Array.from(arguments)

But you rarely use the arguments object directly nowadays thanks to the spread syntax.

What does "export" do in shell programming?

Well, it generally depends on the shell. For bash, it marks the variable as "exportable" meaning that it will show up in the environment for any child processes you run.

Non-exported variables are only visible from the current process (the shell).

From the bash man page:

export [-fn] [name[=word]] ...
export -p

The supplied names are marked for automatic export to the environment of subsequently executed commands.

If the -f option is given, the names refer to functions. If no names are given, or if the -p option is supplied, a list of all names that are exported in this shell is printed.

The -n option causes the export property to be removed from each name.

If a variable name is followed by =word, the value of the variable is set to word.

export returns an exit status of 0 unless an invalid option is encountered, one of the names is not a valid shell variable name, or -f is supplied with a name that is not a function.

You can also set variables as exportable with the typeset command and automatically mark all future variable creations or modifications as such, with set -a.

how to hide keyboard after typing in EditText in android?

int klavStat = 1; // for keyboard soft/hide button
int inType;  // to remeber your default keybort Type

editor - is EditText field

/// metod for onclick button ///
public void keyboard(View view) {
    if (klavStat == 1) {
        klavStat = 0;
        
        inType = editor.getInputType();
        
        InputMethodManager imm = (InputMethodManager)
                getSystemService(Context.INPUT_METHOD_SERVICE);
        imm.toggleSoftInput(0, InputMethodManager.HIDE_NOT_ALWAYS);
     

        editor.setInputType(InputType.TYPE_NULL);

        editor.setTextIsSelectable(true);
    } else {
        klavStat = 1;


        InputMethodManager imm = (InputMethodManager)
                getSystemService(Context.INPUT_METHOD_SERVICE);

        imm.toggleSoftInput(InputMethodManager.SHOW_IMPLICIT, 0);

        editor.setInputType(inType);
    }
}

If you have another EditText Field, you need to watch for focus change.

process.start() arguments

Make sure to use full paths, e.g. not only "video.avi" but the full path to that file.

A simple trick for debugging would be to start a command window using cmd /k <command>instead:

string ffmpegPath = Path.Combine(path, "ffmpeg.exe");
string ffmpegParams = @"-f image2 -i frame%d.jpg -vcodec"
    + @" mpeg4 -b 800k C:\myFolder\video.avi"

Process ffmpeg = new Process();
ffmpeg.StartInfo.FileName = "cmd.exe";
ffmpeg.StartInfo.Arguments = "/k " + ffmpegPath + " " + ffmpegParams
ffmpeg.Start();

This will leave the command window open so that you can easily check the output.

How should I deal with "package 'xxx' is not available (for R version x.y.z)" warning?

I had the same problem (on Linux) which could be solved changing the proxy settings. If you are behind a proxy server check the configuration using Sys.getenv("http_proxy") within R. In my ~/.Renviron I had the following lines (from https://support.rstudio.com/hc/en-us/articles/200488488-Configuring-R-to-Use-an-HTTP-or-HTTPS-Proxy) causing the problem:

http_proxy=https://proxy.dom.com:port
http_proxy_user=user:passwd

Changing it to

http_proxy="http://user:[email protected]:port"

solved the problem. You can do the same for https.

It was not the first thought when I read "package xxx is not available for r version-x-y-z" ...

HTH

set pythonpath before import statements

As also noted in the docs here.
Go to Python X.X/Lib and add these lines to the site.py there,

import sys
sys.path.append("yourpathstring")

This changes your sys.path so that on every load, it will have that value in it..

As stated here about site.py,

This module is automatically imported during initialization. Importing this module will append site-specific paths to the module search path and add a few builtins.

For other possible methods of adding some path to sys.path see these docs

Rails: How can I rename a database column in a Ruby on Rails migration?

Manually we can use the below method:

We can edit the migration manually like:

  • Open app/db/migrate/xxxxxxxxx_migration_file.rb

  • Update hased_password to hashed_password

  • Run the below command

    $> rake db:migrate:down VERSION=xxxxxxxxx
    

Then it will remove your migration:

$> rake db:migrate:up VERSION=xxxxxxxxx

It will add your migration with the updated change.