Programs & Examples On #Parallel extensions

Parallel Extensions is a managed concurrency library included in the .NET 4.0 release.

Parallel.ForEach vs Task.Factory.StartNew

I did a small experiment of running a method "1,000,000,000 (one billion)" times with "Parallel.For" and one with "Task" objects.

I measured the processor time and found Parallel more efficient. Parallel.For divides your task in to small work items and executes them on all the cores parallely in a optimal way. While creating lot of task objects ( FYI TPL will use thread pooling internally) will move every execution on each task creating more stress in the box which is evident from the experiment below.

I have also created a small video which explains basic TPL and also demonstrated how Parallel.For utilizes your core more efficiently http://www.youtube.com/watch?v=No7QqSc5cl8 as compared to normal tasks and threads.

Experiment 1

Parallel.For(0, 1000000000, x => Method1());

Experiment 2

for (int i = 0; i < 1000000000; i++)
{
    Task o = new Task(Method1);
    o.Start();
}

Processor time comparison

How to pass value from <option><select> to form action

with jQuery :
html :

<form method="POST" name="myform" action="index.php?action=contact_agent&agent_id="  onsubmit="SetData()">
  <select name="agent" id="agent">
    <option value="1">Agent Homer</option>
    <option value="2">Agent Lenny</option>
    <option value="3">Agent Carl</option>
  </select>
</form>

jQuery :

$('form').submit(function(){
   $(this).attr('action',$(this).attr('action')+$('#agent').val());
   $(this).submit();
});

javascript :

function SetData(){
   var select = document.getElementById('agent');
   var agent_id = select.options[select.selectedIndex].value;
   document.myform.action = "index.php?action=contact_agent&agent_id="+agent_id ; # or .getAttribute('action')
   myform.submit();
}

How do I print a datetime in the local timezone?

I believe the best way to do this is to use the LocalTimezone class defined in the datetime.tzinfo documentation (goto http://docs.python.org/library/datetime.html#tzinfo-objects and scroll down to the "Example tzinfo classes" section):

Assuming Local is an instance of LocalTimezone

t = datetime.datetime(2009, 7, 10, 18, 44, 59, 193982, tzinfo=utc)
local_t = t.astimezone(Local)

then str(local_t) gives:

'2009-07-11 04:44:59.193982+10:00'

which is what you want.

(Note: this may look weird to you because I'm in New South Wales, Australia which is 10 or 11 hours ahead of UTC)

jQuery Mobile how to check if button is disabled?

$('#StartButton:disabled') ..

Then check if it's undefined.

Plot smooth line with PyPlot

See the scipy.interpolate documentation for some examples.

The following example demonstrates its use, for linear and cubic spline interpolation:

>>> from scipy.interpolate import interp1d

>>> x = np.linspace(0, 10, num=11, endpoint=True)
>>> y = np.cos(-x**2/9.0)
>>> f = interp1d(x, y)
>>> f2 = interp1d(x, y, kind='cubic')

>>> xnew = np.linspace(0, 10, num=41, endpoint=True)
>>> import matplotlib.pyplot as plt
>>> plt.plot(x, y, 'o', xnew, f(xnew), '-', xnew, f2(xnew), '--')
>>> plt.legend(['data', 'linear', 'cubic'], loc='best')
>>> plt.show()

enter image description here

How to query values from xml nodes?

if you have only one xml in your table, you can convert it in 2 steps:

CREATE TABLE Batches( 
   BatchID int,
   RawXml xml 
)

declare @xml xml=(select top 1 RawXml from @Batches)

SELECT  --b.BatchID,
        x.XmlCol.value('(ReportHeader/OrganizationReportReferenceIdentifier)[1]','VARCHAR(100)') AS OrganizationReportReferenceIdentifier,
        x.XmlCol.value('(ReportHeader/OrganizationNumber)[1]','VARCHAR(100)') AS OrganizationNumber
FROM    @xml.nodes('/CasinoDisbursementReportXmlFile/CasinoDisbursementReport') x(XmlCol)

Get error message if ModelState.IsValid fails?

Try

ModelState.Values.First().Errors[0].ErrorMessage

How can I update my ADT in Eclipse?

I had this problem. Since I already had the ADT address I could not follow the suggested fix. The reason why the update was not working in my case is that the ADT address was not checked in the list of "Available updates".

1) Go to eclipse > help > Install new software

2) Click on "Available Software site"

3) Check that you have the ADT address

4) If not add it following the Murtuza Kabul's steps

5) if yes check that the address is checked (checkbox on the left of the address)

I run the update after having launched Eclipse as administrator to be sure that it was not going to have problems accessing the system folders

How do I fix a "Expected Primary-expression before ')' token" error?

showInventory(player); is passing a type as parameter. That's illegal, you need to pass an object.

For example, something like:

player p;
showInventory(p);  

I'm guessing you have something like this:

int main()
{
   player player;
   toDo();
}

which is awful. First, don't name the object the same as your type. Second, in order for the object to be visible inside the function, you'll need to pass it as parameter:

int main()
{
   player p;
   toDo(p);
}

and

std::string toDo(player& p) 
{
    //....
    showInventory(p);
    //....
}

Repository Pattern Step by Step Explanation

As a summary, I would describe the wider impact of the repository pattern. It allows all of your code to use objects without having to know how the objects are persisted. All of the knowledge of persistence, including mapping from tables to objects, is safely contained in the repository.

Very often, you will find SQL queries scattered in the codebase and when you come to add a column to a table you have to search code files to try and find usages of a table. The impact of the change is far-reaching.

With the repository pattern, you would only need to change one object and one repository. The impact is very small.

Perhaps it would help to think about why you would use the repository pattern. Here are some reasons:

  • You have a single place to make changes to your data access

  • You have a single place responsible for a set of tables (usually)

  • It is easy to replace a repository with a fake implementation for testing - so you don't need to have a database available to your unit tests

There are other benefits too, for example, if you were using MySQL and wanted to switch to SQL Server - but I have never actually seen this in practice!

Get size of all tables in database

Here is a sample query to get tables larger than 1GB ordered by size descending.

USE YourDB
GO

DECLARE @Mult float = 8
SET @Mult = @Mult / POWER(2, 20) -- Use POWER(2, 10) for MBs

; WITH CTE AS
(
SELECT
    i.object_id,
    Rows = MAX(p.rows),
    TotalSpaceGB = ROUND(SUM(a.total_pages) * @Mult, 0),
    UsedSpaceGB = ROUND(SUM(a.used_pages) * @Mult, 0)
FROM 
    sys.indexes i
JOIN
    sys.partitions p ON i.object_id = p.object_id AND i.index_id = p.index_id
JOIN
    sys.allocation_units a ON p.partition_id = a.container_id
WHERE
    i.object_id > 255
GROUP BY
    i.object_id
HAVING
    SUM(a.total_pages) * @Mult > 1
)
SELECT 
    SchemaName = s.name,
    TableName = t.name,
    c.TotalSpaceGB,
    c.UsedSpaceGB,
    UnusedSpaceGB = c.TotalSpaceGB - c.UsedSpaceGB,
    [RowCount] = c.Rows
FROM 
    CTE c
JOIN    
    sys.tables t ON t.object_id = c.object_id
JOIN
    sys.schemas s ON t.schema_id = s.schema_id
ORDER BY
    c.TotalSpaceGB DESC

Java FileReader encoding issue

Since Java 11 you may use that:

public FileReader(String fileName, Charset charset) throws IOException;

What does [object Object] mean?

Consider the following example:

const foo = {};
foo[Symbol.toStringTag] = "bar";
console.log("" + foo);

Which outputs

[object bar]

Basically, any object in javascript can define a property with the tag Symbol.toStringTag and override the output.

Behind the scenes construction of a new object in javascript prototypes from some object with a "toString" method. The default object provides this method as a property, and that method internally invokes the tag to determine how to coerce the object to a string. If the tag is present, then it's used, if missing you get "Object".

Should you set Symbol.toStringTag? Maybe. But relying on the string always being [object Object] for "true" objects is not the best idea.

How to split a list by comma not space

You can use:

cat f.csv | sed 's/,/ /g' |  awk '{print $1 " / " $4}'

or

echo "Hello,World,Questions,Answers,bash shell,script" | sed 's/,/ /g' |  awk '{print $1 " / " $4}'

This is the part that replace comma with space

sed 's/,/ /g'

Setting the number of map tasks and reduce tasks

Number of map tasks is directly defined by number of chunks your input is splitted. The size of data chunk (i.e. HDFS block size) is controllable and can be set for an individual file, set of files, directory(-s). So, setting specific number of map tasks in a job is possible but involves setting a corresponding HDFS block size for job's input data. mapred.map.tasks can be used for that too but only if its provided value is greater than number of splits for job's input data.

Controlling number of reducers via mapred.reduce.tasks is correct. However, setting it to zero is a rather special case: the job's output is an concatenation of mappers' outputs (non-sorted). In Matt's answer one can see more ways to set the number of reducers.

php - add + 7 days to date format mm dd, YYYY

yes

$oneweekfromnow = strtotime("+1 week", strtotime("<date-from-db>"));

on another note, why do you have your date in the database like that?

How to replace four spaces with a tab in Sublime Text 2?

create a keybinding for quickest way

{ "keys": ["super+alt+t"], "command": "unexpand_tabs", "args": { "set_translate_tabs": true } }

add this to Preferences > Key Bindings (user) when you press super+alt+t it will convert spaces to tabs

Best way to compare 2 XML documents in Java

AssertJ 1.4+ has specific assertions to compare XML content:

String expectedXml = "<foo />";
String actualXml = "<bar />";
assertThat(actualXml).isXmlEqualTo(expectedXml);

Here is the Documentation

Import and Export Excel - What is the best library?

You could try the following library, it is easy enough and it is just a light wrapper over Microsoft's Open XML SDK (you can even reuse formatting, styles and even entire worksheets from secondary Excel file) : http://officehelper.codeplex.com

Reading JSON from a file?

To add on this, today you are able to use pandas to import json:
https://pandas.pydata.org/pandas-docs/stable/generated/pandas.read_json.html You may want to do a careful use of the orient parameter.

Writing a pandas DataFrame to CSV file

To delimit by a tab you can use the sep argument of to_csv:

df.to_csv(file_name, sep='\t')

To use a specific encoding (e.g. 'utf-8') use the encoding argument:

df.to_csv(file_name, sep='\t', encoding='utf-8')

How can I check if a URL exists via PHP?

Other way to check if a URL is valid or not can be:

<?php

  if (isValidURL("http://www.gimepix.com")) {
      echo "URL is valid...";
  } else {
      echo "URL is not valid...";
  }

  function isValidURL($url) {
      $file_headers = @get_headers($url);
      if (strpos($file_headers[0], "200 OK") > 0) {
         return true;
      } else {
        return false;
      }
  }
?>

Simple Android grid example using RecyclerView with GridLayoutManager (like the old GridView)

Set in RecyclerView initialization

recyclerView.setLayoutManager(new GridLayoutManager(this, 4));

What's the "Content-Length" field in HTTP header?

From this page

The most common use of POST, by far, is to submit HTML form data to CGI scripts. In this case, the Content-Type: header is usually application/x-www-form-urlencoded, and the Content-Length: header gives the length of the URL-encoded form data (here's a note on URL-encoding). The CGI script receives the message body through STDIN, and decodes it. Here's a typical form submission, using POST:

POST /path/script.cgi HTTP/1.0
From: [email protected]
User-Agent: HTTPTool/1.0
Content-Type: application/x-www-form-urlencoded
Content-Length: 32

How to change Label Value using javascript

This will work in Chrome

// get your input
var input = document.getElementById('txt206451');
// get it's (first) label
var label = input.labels[0];
// change it's content
label.textContent = 'thanks'

But after looking, labels doesn't seem to be widely supported..


You can use querySelector

// get txt206451's (first) label
var label = document.querySelector('label[for="txt206451"]');
// change it's content
label.textContent = 'thanks'

Extract elements of list at odd positions

I like List comprehensions because of their Math (Set) syntax. So how about this:

L = [1, 2, 3, 4, 5, 6, 7]
odd_numbers = [y for x,y in enumerate(L) if x%2 != 0]
even_numbers = [y for x,y in enumerate(L) if x%2 == 0]

Basically, if you enumerate over a list, you'll get the index x and the value y. What I'm doing here is putting the value y into the output list (even or odd) and using the index x to find out if that point is odd (x%2 != 0).

Selecting between two dates within a DateTime field - SQL Server

SELECT * 
FROM tbl 
WHERE myDate BETWEEN #date one# AND #date two#;

How do I deal with corrupted Git object files?

Recovering from Repository Corruption is the official answer.

The really short answer is: find uncorrupted objects and copy them.

How to execute a shell script from C in Linux?

It depends on what you want to do with the script (or any other program you want to run).

If you just want to run the script system is the easiest thing to do, but it does some other stuff too, including running a shell and having it run the command (/bin/sh under most *nix).

If you want to either feed the shell script via its standard input or consume its standard output you can use popen (and pclose) to set up a pipe. This also uses the shell (/bin/sh under most *nix) to run the command.

Both of these are library functions that do a lot under the hood, but if they don't meet your needs (or you just want to experiment and learn) you can also use system calls directly. This also allows you do avoid having the shell (/bin/sh) run your command for you.

The system calls of interest are fork, execve, and waitpid. You may want to use one of the library wrappers around execve (type man 3 exec for a list of them). You may also want to use one of the other wait functions (man 2 wait has them all). Additionally you may be interested in the system calls clone and vfork which are related to fork.

fork duplicates the current program, where the only main difference is that the new process gets 0 returned from the call to fork. The parent process gets the new process's process id (or an error) returned.

execve replaces the current program with a new program (keeping the same process id).

waitpid is used by a parent process to wait on a particular child process to finish.

Having the fork and execve steps separate allows programs to do some setup for the new process before it is created (without messing up itself). These include changing standard input, output, and stderr to be different files than the parent process used, changing the user or group of the process, closing files that the child won't need, changing the session, or changing the environmental variables.

You may also be interested in the pipe and dup2 system calls. pipe creates a pipe (with both an input and an output file descriptor). dup2 duplicates a file descriptor as a specific file descriptor (dup is similar but duplicates a file descriptor to the lowest available file descriptor).

Creating a daemon in Linux

You cannot create a process in linux that cannot be killed. The root user (uid=0) can send a signal to a process, and there are two signals which cannot be caught, SIGKILL=9, SIGSTOP=19. And other signals (when uncaught) can also result in process termination.

You may want a more general daemonize function, where you can specify a name for your program/daemon, and a path to run your program (perhaps "/" or "/tmp"). You may also want to provide file(s) for stderr and stdout (and possibly a control path using stdin).

Here are the necessary includes:

#include <stdio.h>    //printf(3)
#include <stdlib.h>   //exit(3)
#include <unistd.h>   //fork(3), chdir(3), sysconf(3)
#include <signal.h>   //signal(3)
#include <sys/stat.h> //umask(3)
#include <syslog.h>   //syslog(3), openlog(3), closelog(3)

And here is a more general function,

int
daemonize(char* name, char* path, char* outfile, char* errfile, char* infile )
{
    if(!path) { path="/"; }
    if(!name) { name="medaemon"; }
    if(!infile) { infile="/dev/null"; }
    if(!outfile) { outfile="/dev/null"; }
    if(!errfile) { errfile="/dev/null"; }
    //printf("%s %s %s %s\n",name,path,outfile,infile);
    pid_t child;
    //fork, detach from process group leader
    if( (child=fork())<0 ) { //failed fork
        fprintf(stderr,"error: failed fork\n");
        exit(EXIT_FAILURE);
    }
    if (child>0) { //parent
        exit(EXIT_SUCCESS);
    }
    if( setsid()<0 ) { //failed to become session leader
        fprintf(stderr,"error: failed setsid\n");
        exit(EXIT_FAILURE);
    }

    //catch/ignore signals
    signal(SIGCHLD,SIG_IGN);
    signal(SIGHUP,SIG_IGN);

    //fork second time
    if ( (child=fork())<0) { //failed fork
        fprintf(stderr,"error: failed fork\n");
        exit(EXIT_FAILURE);
    }
    if( child>0 ) { //parent
        exit(EXIT_SUCCESS);
    }

    //new file permissions
    umask(0);
    //change to path directory
    chdir(path);

    //Close all open file descriptors
    int fd;
    for( fd=sysconf(_SC_OPEN_MAX); fd>0; --fd )
    {
        close(fd);
    }

    //reopen stdin, stdout, stderr
    stdin=fopen(infile,"r");   //fd=0
    stdout=fopen(outfile,"w+");  //fd=1
    stderr=fopen(errfile,"w+");  //fd=2

    //open syslog
    openlog(name,LOG_PID,LOG_DAEMON);
    return(0);
}

Here is a sample program, which becomes a daemon, hangs around, and then leaves.

int
main()
{
    int res;
    int ttl=120;
    int delay=5;
    if( (res=daemonize("mydaemon","/tmp",NULL,NULL,NULL)) != 0 ) {
        fprintf(stderr,"error: daemonize failed\n");
        exit(EXIT_FAILURE);
    }
    while( ttl>0 ) {
        //daemon code here
        syslog(LOG_NOTICE,"daemon ttl %d",ttl);
        sleep(delay);
        ttl-=delay;
    }
    syslog(LOG_NOTICE,"daemon ttl expired");
    closelog();
    return(EXIT_SUCCESS);
}

Note that SIG_IGN indicates to catch and ignore the signal. You could build a signal handler that can log signal receipt, and set flags (such as a flag to indicate graceful shutdown).

Regular expression for only characters a-z, A-Z

With POSIX Bracket Expressions (not supported by Javascript) it can be done this way:

/[:alpha:]+/

Any alpha character A to Z or a to z.

or

/^[[:alpha:]]+$/s

to match strictly with spaces.

Sharing url link does not show thumbnail image on facebook

My site faces same issue too.

Using Facebook debug tool is no help at all. Fetch new data but not IMAGE CACHE.

I forced facebook to clear IMAGE CACHE by add www. into image url. In your case is remove www. and config web server redirect.

 add/remove www. in image url should solve the problem

Avoid Adding duplicate elements to a List C#

If you want to save distinct values into a collection you could try HashSet Class. It will automatically remove the duplicate values and save your coding time. :)

How to run a shell script on a Unix console or Mac terminal?

To run a non-executable sh script, use:

sh myscript

To run a non-executable bash script, use:

bash myscript

To start an executable (which is any file with executable permission); you just specify it by its path:

/foo/bar
/bin/bar
./bar

To make a script executable, give it the necessary permission:

chmod +x bar
./bar

When a file is executable, the kernel is responsible for figuring out how to execte it. For non-binaries, this is done by looking at the first line of the file. It should contain a hashbang:

#! /usr/bin/env bash

The hashbang tells the kernel what program to run (in this case the command /usr/bin/env is ran with the argument bash). Then, the script is passed to the program (as second argument) along with all the arguments you gave the script as subsequent arguments.

That means every script that is executable should have a hashbang. If it doesn't, you're not telling the kernel what it is, and therefore the kernel doesn't know what program to use to interprete it. It could be bash, perl, python, sh, or something else. (In reality, the kernel will often use the user's default shell to interprete the file, which is very dangerous because it might not be the right interpreter at all or it might be able to parse some of it but with subtle behavioural differences such as is the case between sh and bash).

A note on /usr/bin/env

Most commonly, you'll see hash bangs like so:

#!/bin/bash

The result is that the kernel will run the program /bin/bash to interpret the script. Unfortunately, bash is not always shipped by default, and it is not always available in /bin. While on Linux machines it usually is, there are a range of other POSIX machines where bash ships in various locations, such as /usr/xpg/bin/bash or /usr/local/bin/bash.

To write a portable bash script, we can therefore not rely on hard-coding the location of the bash program. POSIX already has a mechanism for dealing with that: PATH. The idea is that you install your programs in one of the directories that are in PATH and the system should be able to find your program when you want to run it by name.

Sadly, you cannot just do this:

#!bash

The kernel won't (some might) do a PATH search for you. There is a program that can do a PATH search for you, though, it's called env. Luckily, nearly all systems have an env program installed in /usr/bin. So we start env using a hardcoded path, which then does a PATH search for bash and runs it so that it can interpret your script:

#!/usr/bin/env bash

This approach has one downside: According to POSIX, the hashbang can have one argument. In this case, we use bash as the argument to the env program. That means we have no space left to pass arguments to bash. So there's no way to convert something like #!/bin/bash -exu to this scheme. You'll have to put set -exu after the hashbang instead.

This approach also has another advantage: Some systems may ship with a /bin/bash, but the user may not like it, may find it's buggy or outdated, and may have installed his own bash somewhere else. This is often the case on OS X (Macs) where Apple ships an outdated /bin/bash and users install an up-to-date /usr/local/bin/bash using something like Homebrew. When you use the env approach which does a PATH search, you take the user's preference into account and use his preferred bash over the one his system shipped with.

SQL How to remove duplicates within select query?

Do you need any other information except the date? If not:

SELECT DISTINCT start_date FROM table;

How can I convert a hex string to a byte array?

Here's a nice fun LINQ example.

public static byte[] StringToByteArray(string hex) {
    return Enumerable.Range(0, hex.Length)
                     .Where(x => x % 2 == 0)
                     .Select(x => Convert.ToByte(hex.Substring(x, 2), 16))
                     .ToArray();
}

Display Yes and No buttons instead of OK and Cancel in Confirm box?

No, it is not possible to change the content of the buttons in the dialog displayed by the confirm function. You can use Javascript to create a dialog that looks similar.

how to make UITextView height dynamic according to text length?

Better yet swift 4 add as an extension:

extension UITextView {
    func resizeForHeight(){
        self.translatesAutoresizingMaskIntoConstraints = true
        self.sizeToFit()
        self.isScrollEnabled = false
    }
}

What is the difference between JAX-RS and JAX-WS?

JAX-WS - is Java API for the XML-Based Web Services - a standard way to develop a Web- Services in SOAP notation (Simple Object Access Protocol).

Calling of the Web Services is performed via remote procedure calls. For the exchange of information between the client and the Web Service is used SOAP protocol. Message exchange between the client and the server performed through XML- based SOAP messages.

Clients of the JAX-WS Web- Service need a WSDL file to generate executable code that the clients can use to call Web- Service.

JAX-RS - Java API for RESTful Web Services. RESTful Web Services are represented as resources and can be identified by Uniform Resource Identifiers (URI). Remote procedure call in this case is represented a HTTP- request and the necessary data is passed as parameters of the query. Web Services RESTful - more flexible, can use several different MIME- types. Typically used for XML data exchange or JSON (JavaScript Object Notation) data exchange...

Is it possible to open developer tools console in Chrome on Android phone?

Kiwi Browser is mobile Chromium and allows installing extensions. Install Kiwi and then install "Mini JS console" Chrome extension(just search in Google and install from Chrome extensions website, uBlock also works ;). It will become available in Kiwi menu at the bottom and will show the console output for the current page.

printf and long double

In C99 the length modifier for long double seems to be L and not l. man fprintf (or equivalent for windows) should tell you for your particular platform.

get string from right hand side

If you want to list last 3 chars, simplest way is

 select substr('123456',-3) from dual;

Swift: Reload a View Controller

In Swift 4:

self.view.layoutIfNeeded()

Adding backslashes without escaping [Python]

There is no extra backslash, it's just formatted that way in the interactive environment. Try:

print string

Then you can see that there really is no extra backslash.

jQuery remove all list items from an unordered list

$("ul").empty() works fine. Is there some other error?

_x000D_
_x000D_
$('input').click(function() {_x000D_
  $('ul').empty()_x000D_
});
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>_x000D_
<ul>_x000D_
  <li>test</li>_x000D_
  <li>test</li>_x000D_
</ul>_x000D_
_x000D_
<input type="button" value="click me" />
_x000D_
_x000D_
_x000D_

http://jsfiddle.net/infernalbadger/D5ss8/

Remove grid, background color, and top and right borders from ggplot2

Here's an extremely simple answer

yourPlot +
  theme(
    panel.border = element_blank(), 
    panel.grid.major = element_blank(),
    panel.grid.minor = element_blank(), 
    axis.line = element_line(colour = "black")
    )

It's that easy. Source: the end of this article

How to use __DATE__ and __TIME__ predefined macros in as two integers, then stringify?

If you can use a C++ compiler to build the object file that you want to contain your version string, then we can do exactly what you want! The only magic here is that C++ allows you to use expressions to statically initialize an array, while C doesn't. The expressions need to be fully computable at compile time, but these expressions are, so it's no problem.

We build up the version string one byte at a time, and get exactly what we want.

// source file version_num.h

#ifndef VERSION_NUM_H

#define VERSION_NUM_H


#define VERSION_MAJOR 1
#define VERSION_MINOR 4


#endif // VERSION_NUM_H

// source file build_defs.h

#ifndef BUILD_DEFS_H

#define BUILD_DEFS_H


// Example of __DATE__ string: "Jul 27 2012"
//                              01234567890

#define BUILD_YEAR_CH0 (__DATE__[ 7])
#define BUILD_YEAR_CH1 (__DATE__[ 8])
#define BUILD_YEAR_CH2 (__DATE__[ 9])
#define BUILD_YEAR_CH3 (__DATE__[10])


#define BUILD_MONTH_IS_JAN (__DATE__[0] == 'J' && __DATE__[1] == 'a' && __DATE__[2] == 'n')
#define BUILD_MONTH_IS_FEB (__DATE__[0] == 'F')
#define BUILD_MONTH_IS_MAR (__DATE__[0] == 'M' && __DATE__[1] == 'a' && __DATE__[2] == 'r')
#define BUILD_MONTH_IS_APR (__DATE__[0] == 'A' && __DATE__[1] == 'p')
#define BUILD_MONTH_IS_MAY (__DATE__[0] == 'M' && __DATE__[1] == 'a' && __DATE__[2] == 'y')
#define BUILD_MONTH_IS_JUN (__DATE__[0] == 'J' && __DATE__[1] == 'u' && __DATE__[2] == 'n')
#define BUILD_MONTH_IS_JUL (__DATE__[0] == 'J' && __DATE__[1] == 'u' && __DATE__[2] == 'l')
#define BUILD_MONTH_IS_AUG (__DATE__[0] == 'A' && __DATE__[1] == 'u')
#define BUILD_MONTH_IS_SEP (__DATE__[0] == 'S')
#define BUILD_MONTH_IS_OCT (__DATE__[0] == 'O')
#define BUILD_MONTH_IS_NOV (__DATE__[0] == 'N')
#define BUILD_MONTH_IS_DEC (__DATE__[0] == 'D')


#define BUILD_MONTH_CH0 \
    ((BUILD_MONTH_IS_OCT || BUILD_MONTH_IS_NOV || BUILD_MONTH_IS_DEC) ? '1' : '0')

#define BUILD_MONTH_CH1 \
    ( \
        (BUILD_MONTH_IS_JAN) ? '1' : \
        (BUILD_MONTH_IS_FEB) ? '2' : \
        (BUILD_MONTH_IS_MAR) ? '3' : \
        (BUILD_MONTH_IS_APR) ? '4' : \
        (BUILD_MONTH_IS_MAY) ? '5' : \
        (BUILD_MONTH_IS_JUN) ? '6' : \
        (BUILD_MONTH_IS_JUL) ? '7' : \
        (BUILD_MONTH_IS_AUG) ? '8' : \
        (BUILD_MONTH_IS_SEP) ? '9' : \
        (BUILD_MONTH_IS_OCT) ? '0' : \
        (BUILD_MONTH_IS_NOV) ? '1' : \
        (BUILD_MONTH_IS_DEC) ? '2' : \
        /* error default */    '?' \
    )

#define BUILD_DAY_CH0 ((__DATE__[4] >= '0') ? (__DATE__[4]) : '0')
#define BUILD_DAY_CH1 (__DATE__[ 5])



// Example of __TIME__ string: "21:06:19"
//                              01234567

#define BUILD_HOUR_CH0 (__TIME__[0])
#define BUILD_HOUR_CH1 (__TIME__[1])

#define BUILD_MIN_CH0 (__TIME__[3])
#define BUILD_MIN_CH1 (__TIME__[4])

#define BUILD_SEC_CH0 (__TIME__[6])
#define BUILD_SEC_CH1 (__TIME__[7])


#if VERSION_MAJOR > 100

#define VERSION_MAJOR_INIT \
    ((VERSION_MAJOR / 100) + '0'), \
    (((VERSION_MAJOR % 100) / 10) + '0'), \
    ((VERSION_MAJOR % 10) + '0')

#elif VERSION_MAJOR > 10

#define VERSION_MAJOR_INIT \
    ((VERSION_MAJOR / 10) + '0'), \
    ((VERSION_MAJOR % 10) + '0')

#else

#define VERSION_MAJOR_INIT \
    (VERSION_MAJOR + '0')

#endif

#if VERSION_MINOR > 100

#define VERSION_MINOR_INIT \
    ((VERSION_MINOR / 100) + '0'), \
    (((VERSION_MINOR % 100) / 10) + '0'), \
    ((VERSION_MINOR % 10) + '0')

#elif VERSION_MINOR > 10

#define VERSION_MINOR_INIT \
    ((VERSION_MINOR / 10) + '0'), \
    ((VERSION_MINOR % 10) + '0')

#else

#define VERSION_MINOR_INIT \
    (VERSION_MINOR + '0')

#endif



#endif // BUILD_DEFS_H

// source file main.c

#include "version_num.h"
#include "build_defs.h"

// want something like: 1.4.1432.2234

const unsigned char completeVersion[] =
{
    VERSION_MAJOR_INIT,
    '.',
    VERSION_MINOR_INIT,
    '-', 'V', '-',
    BUILD_YEAR_CH0, BUILD_YEAR_CH1, BUILD_YEAR_CH2, BUILD_YEAR_CH3,
    '-',
    BUILD_MONTH_CH0, BUILD_MONTH_CH1,
    '-',
    BUILD_DAY_CH0, BUILD_DAY_CH1,
    'T',
    BUILD_HOUR_CH0, BUILD_HOUR_CH1,
    ':',
    BUILD_MIN_CH0, BUILD_MIN_CH1,
    ':',
    BUILD_SEC_CH0, BUILD_SEC_CH1,
    '\0'
};


#include <stdio.h>

int main(int argc, char **argv)
{
    printf("%s\n", completeVersion);
    // prints something similar to: 1.4-V-2013-05-09T15:34:49
}

This isn't exactly the format you asked for, but I still don't fully understand how you want days and hours mapped to an integer. I think it's pretty clear how to make this produce any desired string.

.NET obfuscation tools/strategy

I have been using smartassembly. Basically, you pick a dll and it returns it obfuscated. It seems to work fine and I've had no problems so far. Very, very easy to use.

Find row where values for column is maximal in a pandas DataFrame

df.iloc[df['columnX'].argmax()]

argmax() would provide the index corresponding to the max value for the columnX. iloc can be used to get the row of the DataFrame df for this index.

org.hibernate.hql.internal.ast.QuerySyntaxException: table is not mapped

It means your table is not mapped to the JPA. Either Name of the table is wrong (Maybe case sensitive), or you need to put an entry in the XML file.

Happy Coding :)

How do I wrap text in a span?

I've got a solution that should work in IE6 (and definitely works in 7+ & FireFox/Chrome).
You were on the right track using a span, but the use of a ul was wrong and the css wasn't right.

Try this

<a class="htooltip" href="#">
    Notes

    <span>
        Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Maecenas porttitor congue massa. Fusce posuere, magna sed pulvinar ultricies, purus lectus malesuada libero, sit amet commodo magna eros quis urna. Nunc viverra imperdiet enim. Fusce est. Vivamus a tellus. Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas. Proin pharetra nonummy pede. Mauris et orci.
    </span>
</a>
.htooltip, .htooltip:visited, .tooltip:active {
    color: #0077AA;
    text-decoration: none;
}

.htooltip:hover {
    color: #0099CC;
}

.htooltip span {
    display : none;
    position: absolute;
    background-color: black;
    color: #fff;
    padding: 5px 10px 5px 40px;
    text-decoration: none;
    width: 350px;
    z-index: 10;
}

.htooltip:hover span {
    display: block;
}

Everyone was going about this the wrong way. The code isn't valid, ul's cant go in a's, p's can't go in a's, div's cant go in a's, just use a span (remembering to make it display as a block so it will wrap as if it were a div/p etc).

How to check Oracle database for long running queries

You can use the v$sql_monitor view to find queries that are running longer than 5 seconds. This may only be available in Enterprise versions of Oracle. For example this query will identify slow running queries from my TEST_APP service:

select to_char(sql_exec_start, 'dd-Mon hh24:mi'), (elapsed_time / 1000000) run_time,
       cpu_time, sql_id, sql_text 
from   v$sql_monitor
where  service_name = 'TEST_APP'
order  by 1 desc;

Note elapsed_time is in microseconds so / 1000000 to get something more readable

How can I get the UUID of my Android phone in an application?

As Dave Webb mentions, the Android Developer Blog has an article that covers this. Their preferred solution is to track app installs rather than devices, and that will work well for most use cases. The blog post will show you the necessary code to make that work, and I recommend you check it out.

However, the blog post goes on to discuss solutions if you need a device identifier rather than an app installation identifier. I spoke with someone at Google to get some additional clarification on a few items in the event that you need to do so. Here's what I discovered about device identifiers that's NOT mentioned in the aforementioned blog post:

  • ANDROID_ID is the preferred device identifier. ANDROID_ID is perfectly reliable on versions of Android <=2.1 or >=2.3. Only 2.2 has the problems mentioned in the post.
  • Several devices by several manufacturers are affected by the ANDROID_ID bug in 2.2.
  • As far as I've been able to determine, all affected devices have the same ANDROID_ID, which is 9774d56d682e549c. Which is also the same device id reported by the emulator, btw.
  • Google believes that OEMs have patched the issue for many or most of their devices, but I was able to verify that as of the beginning of April 2011, at least, it's still quite easy to find devices that have the broken ANDROID_ID.
  • When a device has multiple users (available on certain devices running Android 4.2 or higher), each user appears as a completely separate device, so the ANDROID_ID value is unique to each user.

Based on Google's recommendations, I implemented a class that will generate a unique UUID for each device, using ANDROID_ID as the seed where appropriate, falling back on TelephonyManager.getDeviceId() as necessary, and if that fails, resorting to a randomly generated unique UUID that is persisted across app restarts (but not app re-installations).

Note that for devices that have to fallback on the device ID, the unique ID WILL persist across factory resets. This is something to be aware of. If you need to ensure that a factory reset will reset your unique ID, you may want to consider falling back directly to the random UUID instead of the device ID.

Again, this code is for a device ID, not an app installation ID. For most situations, an app installation ID is probably what you're looking for. But if you do need a device ID, then the following code will probably work for you.

import android.content.Context;
import android.content.SharedPreferences;
import android.provider.Settings.Secure;
import android.telephony.TelephonyManager;

import java.io.UnsupportedEncodingException;
import java.util.UUID;

public class DeviceUuidFactory {
    protected static final String PREFS_FILE = "device_id.xml";
    protected static final String PREFS_DEVICE_ID = "device_id";

    protected static UUID uuid;



    public DeviceUuidFactory(Context context) {

        if( uuid ==null ) {
            synchronized (DeviceUuidFactory.class) {
                if( uuid == null) {
                    final SharedPreferences prefs = context.getSharedPreferences( PREFS_FILE, 0);
                    final String id = prefs.getString(PREFS_DEVICE_ID, null );

                    if (id != null) {
                        // Use the ids previously computed and stored in the prefs file
                        uuid = UUID.fromString(id);

                    } else {

                        final String androidId = Secure.getString(context.getContentResolver(), Secure.ANDROID_ID);

                        // Use the Android ID unless it's broken, in which case fallback on deviceId,
                        // unless it's not available, then fallback on a random number which we store
                        // to a prefs file
                        try {
                            if (!"9774d56d682e549c".equals(androidId)) {
                                uuid = UUID.nameUUIDFromBytes(androidId.getBytes("utf8"));
                            } else {
                                final String deviceId = ((TelephonyManager) context.getSystemService( Context.TELEPHONY_SERVICE )).getDeviceId();
                                uuid = deviceId!=null ? UUID.nameUUIDFromBytes(deviceId.getBytes("utf8")) : UUID.randomUUID();
                            }
                        } catch (UnsupportedEncodingException e) {
                            throw new RuntimeException(e);
                        }

                        // Write the value out to the prefs file
                        prefs.edit().putString(PREFS_DEVICE_ID, uuid.toString() ).commit();

                    }

                }
            }
        }

    }


    /**
     * Returns a unique UUID for the current android device.  As with all UUIDs, this unique ID is "very highly likely"
     * to be unique across all Android devices.  Much more so than ANDROID_ID is.
     *
     * The UUID is generated by using ANDROID_ID as the base key if appropriate, falling back on
     * TelephonyManager.getDeviceID() if ANDROID_ID is known to be incorrect, and finally falling back
     * on a random UUID that's persisted to SharedPreferences if getDeviceID() does not return a
     * usable value.
     *
     * In some rare circumstances, this ID may change.  In particular, if the device is factory reset a new device ID
     * may be generated.  In addition, if a user upgrades their phone from certain buggy implementations of Android 2.2
     * to a newer, non-buggy version of Android, the device ID may change.  Or, if a user uninstalls your app on
     * a device that has neither a proper Android ID nor a Device ID, this ID may change on reinstallation.
     *
     * Note that if the code falls back on using TelephonyManager.getDeviceId(), the resulting ID will NOT
     * change after a factory reset.  Something to be aware of.
     *
     * Works around a bug in Android 2.2 for many devices when using ANDROID_ID directly.
     *
     * @see http://code.google.com/p/android/issues/detail?id=10603
     *
     * @return a UUID that may be used to uniquely identify your device for most purposes.
     */
    public UUID getDeviceUuid() {
        return uuid;
    }
}

combining results of two select statements

While it is possible to combine the results, I would advise against doing so.

You have two fundamentally different types of queries that return a different number of rows, a different number of columns and different types of data. It would be best to leave it as it is - two separate queries.

Copy Files from Windows to the Ubuntu Subsystem

You should be able to access your windows system under the /mnt directory. For example inside of bash, use this to get to your pictures directory:

cd /mnt/c/Users/<ubuntu.username>/Pictures

Hope this helps!

Separating class code into a header and cpp file

Basically a modified syntax of function declaration/definitions:

a2dd.h

class A2DD
{
private:
  int gx;
  int gy;

public:
  A2DD(int x,int y);

  int getSum();
};

a2dd.cpp

A2DD::A2DD(int x,int y)
{
  gx = x;
  gy = y;
}

int A2DD::getSum()
{
  return gx + gy;
}

Could not reserve enough space for object heap to start JVM

It looks like the machine you're trying to run this on has only 256 MB memory.

Maybe the JVM tries to allocate a large, contiguous block of 64 MB memory. The 192 MB that you have free might be fragmented into smaller pieces, so that there is no contiguous block of 64 MB free to allocate.

Try starting your Java program with a smaller heap size, for example:

java -Xms16m ...

IF EXISTS in T-SQL

There's no need for "else" in this case:

IF EXISTS(SELECT *  FROM  table1  WHERE Name='John' ) return 1
return 0

How can I select the first day of a month in SQL?

I personal recommended that the sql below because when i try use date function in the condition clause, its slow down my query speed very much.

anyway feel free to try this.

select CONCAT(DATEPART(YYYY,@mydate),'-',DATEPART(MM,@mydate),'-01')

How to implement a lock in JavaScript

JavaScript is, with a very few exceptions (XMLHttpRequest onreadystatechange handlers in some versions of Firefox) event-loop concurrent. So you needn't worry about locking in this case.

JavaScript has a concurrency model based on an "event loop". This model is quite different than the model in other languages like C or Java.

...

A JavaScript runtime contains a message queue, which is a list of messages to be processed. To each message is associated a function. When the stack is empty, a message is taken out of the queue and processed. The processing consists of calling the associated function (and thus creating an initial stack frame) The message processing ends when the stack becomes empty again.

...

Each message is processed completely before any other message is processed. This offers some nice properties when reasoning about your program, including the fact that whenever a function runs, it cannot be pre-empted and will run entirely before any other code runs (and can modify data the function manipulates). This differs from C, for instance, where if a function runs in a thread, it can be stopped at any point to run some other code in another thread.

A downside of this model is that if a message takes too long to complete, the web application is unable to process user interactions like click or scroll. The browser mitigates this with the "a script is taking too long to run" dialog. A good practice to follow is to make message processing short and if possible cut down one message into several messages.

For more links on event-loop concurrency, see E

How to create NSIndexPath for TableView

Use [NSIndexPath indexPathForRow:inSection:] to quickly create an index path.

Edit: In Swift 3:

let indexPath = IndexPath(row: rowIndex, section: sectionIndex)

Swift 5

IndexPath(row: 0, section: 0)

What is the most useful script you've written for everyday life?

A perl script that scrapes my local Craigslist, by selected categories, in to a SQL DB which I can then query against.

V2 of this updates the DB with a timer and alerts me if I have a match on any of the queries, basically providing me with a background agent for CL.

Spring: return @ResponseBody "ResponseEntity<List<JSONObject>>"

Instead of

return new ResponseEntity<JSONObject>(entities, HttpStatus.OK);

try

return new ResponseEntity<List<JSONObject>>(entities, HttpStatus.OK);

Chrome & Safari Error::Not allowed to load local resource: file:///D:/CSS/Style.css

You wont be able to access a local resource from your aspx page (web server). Have you tried a relative path from your aspx page to your css file like so...

<link rel="stylesheet" media="all" href="/CSS/Style.css" type="text/css" />

The above assumes that you have a folder called CSS in the root of your website like this:

http://www.website.com/CSS/Style.css

Split string into strings by length?

Here are two generic approaches. Probably worth adding to your own lib of reusables. First one requires the item to be sliceable and second one works with any iterables (but requires their constructor to accept iterable).

def split_bylen(item, maxlen):
    '''
    Requires item to be sliceable (with __getitem__ defined)
    '''
    return [item[ind:ind+maxlen] for ind in range(0, len(item), maxlen)]
    #You could also replace outer [ ] brackets with ( ) to use as generator.

def split_bylen_any(item, maxlen, constructor=None):
    '''
    Works with any iterables.
    Requires item's constructor to accept iterable or alternatively 
    constructor argument could be provided (otherwise use item's class)
    '''
    if constructor is None: constructor = item.__class__
    return [constructor(part) for part in zip(* ([iter(item)] * maxlen))]
    #OR: return map(constructor, zip(* ([iter(item)] * maxlen)))
    #    which would be faster if you need an iterable, not list

So, in topicstarter's case, the usage is:

string = 'Baboons love bananas'
parts = 5
splitlen = -(-len(string) // parts) # is alternative to math.ceil(len/parts)

first_method = split_bylen(string, splitlen)
#Result :['Babo', 'ons ', 'love', ' ban', 'anas']

second_method = split_bylen_any(string, splitlen, constructor=''.join)
#Result :['Babo', 'ons ', 'love', ' ban', 'anas']

java.net.MalformedURLException: no protocol on URL based on a string modified with URLEncoder

Thanks to Erhun's answer I finally realised that my JSON mapper was returning the quotation marks around my data too! I needed to use "asText()" instead of "toString()"

It's not an uncommon issue - one's brain doesn't see anything wrong with the correct data, surrounded by quotes!

discoveryJson.path("some_endpoint").toString();
"https://what.the.com/heck"

discoveryJson.path("some_endpoint").asText();
https://what.the.com/heck

How can I get date in application run by node.js?

You do that as you would in a browser:

_x000D_
_x000D_
    var datetime = new Date();_x000D_
    console.log(datetime);
_x000D_
_x000D_
_x000D_

Download JSON object as a file from browser

Simple, clean solution for those who only target modern browsers:

function downloadTextFile(text, name) {
  const a = document.createElement('a');
  const type = name.split(".").pop();
  a.href = URL.createObjectURL( new Blob([text], { type:`text/${type === "txt" ? "plain" : type}` }) );
  a.download = name;
  a.click();
}

downloadTextFile(JSON.stringify(myObj), 'myObj.json');

Go Back to Previous Page

I think button onclick="history.back();" is one way to solve the problem. But it might not work in the following cases.

  1. If the page gets refreshed or reloaded.

  2. If the user opens the link in a new page.

To overcome these, the following code could be used if you know which page you have to return to. E.g. If you have a no of links on one page and the back button is to be used to return to that page.

<input type="button" onclick="document.location.href='filename';" value="Back" name="button" class="btn">

Setting up PostgreSQL ODBC on Windows

Please note that you must install the driver for the version of your software client(MS access) not the version of the OS. that's mean that if your MS Access is a 32-bits version,you must install a 32-bit odbc driver. regards

Java ArrayList how to add elements at the beginning

List has the method add(int, E), so you can use:

list.add(0, yourObject);

Afterwards you can delete the last element with:

if(list.size() > 10)
    list.remove(list.size() - 1);

However, you might want to rethink your requirements or use a different data structure, like a Queue

EDIT

Maybe have a look at Apache's CircularFifoQueue:

CircularFifoQueue is a first-in first-out queue with a fixed size that replaces its oldest element if full.

Just initialize it with you maximum size:

CircularFifoQueue queue = new CircularFifoQueue(10);

How Should I Declare Foreign Key Relationships Using Code First Entity Framework (4.1) in MVC3?

You can define foreign key by:

public class Parent
{
   public int Id { get; set; }
   public virtual ICollection<Child> Childs { get; set; }
}

public class Child
{
   public int Id { get; set; }
   // This will be recognized as FK by NavigationPropertyNameForeignKeyDiscoveryConvention
   public int ParentId { get; set; } 
   public virtual Parent Parent { get; set; }
}

Now ParentId is foreign key property and defines required relation between child and existing parent. Saving the child without exsiting parent will throw exception.

If your FK property name doesn't consists of the navigation property name and parent PK name you must either use ForeignKeyAttribute data annotation or fluent API to map the relation

Data annotation:

// The name of related navigation property
[ForeignKey("Parent")]
public int ParentId { get; set; }

Fluent API:

modelBuilder.Entity<Child>()
            .HasRequired(c => c.Parent)
            .WithMany(p => p.Childs)
            .HasForeignKey(c => c.ParentId);

Other types of constraints can be enforced by data annotations and model validation.

Edit:

You will get an exception if you don't set ParentId. It is required property (not nullable). If you just don't set it it will most probably try to send default value to the database. Default value is 0 so if you don't have customer with Id = 0 you will get an exception.

How to make IPython notebook matplotlib plot inline

Use the %pylab inline magic command.

Format Date/Time in XAML in Silverlight

<TextBlock Text="{Binding Date, StringFormat='{}{0:MM/dd/yyyy a\\t h:mm tt}'}" />

will return you

04/07/2011 at 1:28 PM (-04)

Convert String to Uri

You can parse a String to a Uri by using Uri.parse() as shown below:

Uri myUri = Uri.parse("http://stackoverflow.com");

The following is an example of how you can use your newly created Uri in an implicit intent. To be viewed in a browser on the users phone.

// Creates a new Implicit Intent, passing in our Uri as the second paramater.
Intent webIntent = new Intent(Intent.ACTION_VIEW, myUri);

// Checks to see if there is an Activity capable of handling the intent
if (webIntent.resolveActivity(getPackageManager()) != null){
    startActivity(webIntent);
}

NB: There is a difference between Androids URI and Uri.

Get the string within brackets in Python

You can also use

re.findall(r"\[([A-Za-z0-9_]+)\]", string)

if there are many occurrences that you would like to find.

See also for more info: How can I find all matches to a regular expression in Python?

MVC Form not able to post List of objects

Please read this: http://haacked.com/archive/2008/10/23/model-binding-to-a-list.aspx
You should set indicies for your html elements "name" attributes like planCompareViewModel[0].PlanId, planCompareViewModel[1].PlanId to make binder able to parse them into IEnumerable.
Instead of @foreach (var planVM in Model) use for loop and render names with indexes.

jquery/javascript convert date string to date

I used the javascript date funtion toLocaleDateString to get

var Today = new Date();
var r = Today.toLocaleDateString();

The result of r will be

11/29/2016

More info at: http://www.w3schools.com/jsref/jsref_tolocaledatestring.asp

Python Threading String Arguments

I hope to provide more background knowledge here.

First, constructor signature of the of method threading::Thread:

class threading.Thread(group=None, target=None, name=None, args=(), kwargs={}, *, daemon=None)

args is the argument tuple for the target invocation. Defaults to ().

Second, A quirk in Python about tuple:

Empty tuples are constructed by an empty pair of parentheses; a tuple with one item is constructed by following a value with a comma (it is not sufficient to enclose a single value in parentheses).

On the other hand, a string is a sequence of characters, like 'abc'[1] == 'b'. So if send a string to args, even in parentheses (still a sting), each character will be treated as a single parameter.

However, Python is so integrated and is not like JavaScript where extra arguments can be tolerated. Instead, it throws an TypeError to complain.

Form Submission without page refresh

<script type="text/javascript">
    var frm = $('#myform');
    frm.submit(function (ev) {
        $.ajax({
            type: frm.attr('method'),
            url: frm.attr('action'),
            data: frm.serialize(),
            success: function (data) {
                alert('ok');
            }
        });

        ev.preventDefault();
    });
</script>

<form id="myform" action="/your_url" method="post">
    ...
</form>

Remove non-numeric characters (except periods and commas) from a string

You could use filter_var to remove all illegal characters except digits, dot and the comma.

  • The FILTER_SANITIZE_NUMBER_FLOAT filter is used to remove all non-numeric character from the string.
  • FILTER_FLAG_ALLOW_FRACTION is allowing fraction separator " . "
  • The purpose of FILTER_FLAG_ALLOW_THOUSAND to get comma from the string.

Code

$var1 = '12.322,11T';

echo filter_var($var1, FILTER_SANITIZE_NUMBER_FLOAT, FILTER_FLAG_ALLOW_FRACTION | FILTER_FLAG_ALLOW_THOUSAND);

Output

12.322,11

To read more about filter_var() and Sanitize filters

How to return a file using Web API?

Another way to download file is to write the stream content to the response's body directly:

[HttpGet("pdfstream/{id}")]
public async Task  GetFile(long id)
{        
    var stream = GetStream(id);
    Response.StatusCode = (int)HttpStatusCode.OK;
    Response.Headers.Add( HeaderNames.ContentDisposition, $"attachment; filename=\"{Guid.NewGuid()}.pdf\"" );
    Response.Headers.Add( HeaderNames.ContentType, "application/pdf"  );            
    await stream.CopyToAsync(Response.Body);
    await Response.Body.FlushAsync();           
}

React Native add bold or italics to single words in <Text> field

You can use <Text> like a container for your other text components. This is example:

...
<Text>
  <Text>This is a sentence</Text>
  <Text style={{fontWeight: "bold"}}> with</Text>
  <Text> one word in bold</Text>
</Text>
...

Here is an example.

How to get the last five characters of a string using Substring() in C#?

e.g.

string str = null;
string retString = null;
str = "This is substring test";
retString = str.Substring(8, 9);

This return "substring"

C# substring sample source

Windows batch files: .bat vs .cmd?

From this news group posting by Mark Zbikowski himself:

The differences between .CMD and .BAT as far as CMD.EXE is concerned are: With extensions enabled, PATH/APPEND/PROMPT/SET/ASSOC in .CMD files will set ERRORLEVEL regardless of error. .BAT sets ERRORLEVEL only on errors.

In other words, if ERRORLEVEL is set to non-0 and then you run one of those commands, the resulting ERRORLEVEL will be:

  • left alone at its non-0 value in a .bat file
  • reset to 0 in a .cmd file.

What is the difference between JavaScript and jQuery?

jQuery was written using JavaScript, and is a library to be used by JavaScript. You cannot learn jQuery without learning JavaScript.

Likely, you'll want to learn and use both of them. go through following breif diffrence http://www.slideshare.net/umarali1981/difference-between-java-script-and-jquery

SQL Add foreign key to existing column

In the future.

ALTER TABLE Employees
ADD UserID int;

ALTER TABLE Employees
ADD CONSTRAINT FK_ActiveDirectories_UserID FOREIGN KEY (UserID)
    REFERENCES ActiveDirectories(id);

ASP.NET MVC 5 - Identity. How to get current ApplicationUser

In case someone is working with Identity users in web forms, I got it working by doing so:

var manager = Context.GetOwinContext().GetUserManager<ApplicationUserManager>();
var user = manager.FindById(User.Identity.GetUserId());

Set a form's action attribute when submitting?

You can try this:

_x000D_
_x000D_
<form action="/home">_x000D_
  _x000D_
  <input type="submit" value="cancel">_x000D_
  _x000D_
  <input type="submit" value="login" formaction="/login">_x000D_
  <input type="submit" value="signup" formaction="/signup">_x000D_
  _x000D_
</form>
_x000D_
_x000D_
_x000D_

Storing money in a decimal column - what precision and scale?

I would think that for a large part your or your client's requirements should dictate what precision and scale to use. For example, for the e-commerce website I am working on that deals with money in GBP only, I have been required to keep it to Decimal( 6, 2 ).

Artisan migrate could not find driver

In your php.ini configuration file simply uncomment the extension:

;extension=pdo_mysql

(You can find your php.ini file in the php folder where your server is installed.)

make this to

extension=pdo_mysql

now you need to configure your .env file in find DB_DATABASE= write in that database name which you used than migrate like if i used my database and database name is "abc" than i need to write there DB_DATABASE=abc and save that .env file and run command again

php artisan migrate

so after run than you got some msg like as:

php artisan migrate
Migration table created successfully.

Get list of filenames in folder with Javascript

I made a different route for every file in a particular directory. Therefore, going to that path meant opening that file.

function getroutes(list){
list.forEach(function(element) {
  app.get("/"+ element,  function(req, res) {
    res.sendFile(__dirname + "/public/extracted/" + element);
  });
});

I called this function passing the list of filename in the directory __dirname/public/extracted and it created a different route for each filename which I was able to render on server side.

Unable to verify leaf signature

Just putting this here in case it helps someone, my case was different and a bit of an odd mix. I was getting this on a request that was accessed via superagent - the problem had nothing to do with certificates (which were setup properly) and all to do with the fact that I was then passing the superagent result through the async module's waterfall callback. To fix: Instead of passing the entire result, just pass result.body through the waterfall's callback.

Subtracting two lists in Python

Python 2.7 and 3.2 added the collections.Counter class, which is a dictionary subclass that maps elements to the number of occurrences of the element. This can be used as a multiset. You can do something like this:

from collections import Counter
a = Counter([0, 1, 2, 1, 0])
b = Counter([0, 1, 1])
c = a - b  # ignores items in b missing in a

print(list(c.elements()))  # -> [0, 2]

As well, if you want to check that every element in b is in a:

# a[key] returns 0 if key not in a, instead of raising an exception
assert all(a[key] >= b[key] for key in b)

But since you are stuck with 2.5, you could try importing it and define your own version if that fails. That way you will be sure to get the latest version if it is available, and fall back to a working version if not. You will also benefit from speed improvements if if gets converted to a C implementation in the future.

try:
   from collections import Counter
except ImportError:
    class Counter(dict):
       ...

You can find the current Python source here.

Get table names using SELECT statement in MySQL

if we have multiple databases and we need to select all tables for a particular database we can use TABLE_SCHEMA to define database name as:

select table_name from information_schema.tables where TABLE_SCHEMA='dbname';

How to add google-play-services.jar project dependency so my project will run and present map

The quick start guide that keyboardsurfer references will work if you need to get your project to build properly, but it leaves you with a dummy google-play-services project in your Eclipse workspace, and it doesn't properly link Eclipse to the Google Play Services Javadocs.

Here's what I did instead:

  1. Install the Google Play Services SDK using the instructions in the Android Maps V2 Quick Start referenced above, or the instructions to Setup Google Play Services SDK, but do not follow the instructions to add Google Play Services into your project.

  2. Right click on the project in the Package Explorer, select Properties to open the properties for your project.

  3. (Only if you already followed the instructions in the quick start guide!) Remove the dependency on the google-play-services project:

    • Click on the Android category and remove the reference to the google-play-services project.

    • Click on the Java Build Path category, then the Projects tab and remove the reference to the google-play-services project.

  4. Click on the Java Build Path category, then the Libraries tab.

  5. Click Add External JARs... and select the google-play-services.jar file. This should be in [Your ADT directory]\sdk\extras\google\google_play_services\libproject\google-play-services_lib\libs.

  6. Click on the arrow next to the new google-play-services.jar entry, and select the Javadoc Location item.

  7. Click Edit... and select the folder containing the Google Play Services Javadocs. This should be in [Your ADT directory]\sdk\extras\google\google_play_services\docs\reference.

  8. Still in the Java Build Path category, click on the Order and Export tab. Check the box next to the google-play-services.jar entry.

  9. Click OK to save your project properties.

Your project should now have access to the Google Play Services library, and the Javadocs should display properly in Eclipse.

intl extension: installing php_intl.dll

The package is already included in the extensions for PHP 7.2 and above and you just need to uncomment the following line in php.ini

extension=intl

download and install visual studio 2008

https://www.microsoft.com/en-us/download/details.aspx?id=14258

which leads to:

Microsoft® Visual Studio Team System 2008 Database Edition GDR R2

Hope this is helpfull

postgresql - sql - count of `true` values

SELECT count(*)         -- or count(myCol)
FROM   <table name>     -- replace <table name> with your table
WHERE  myCol = true;

Here's a way with Windowing Function:

SELECT DISTINCT *, count(*) over(partition by myCol)
FROM   <table name>;

-- Outputs:
-- --------------
-- myCol | count
-- ------+-------
--  f    |  2
--  t    |  3
--       |  1

How to redirect user's browser URL to a different page in Nodejs?

If you are using Express, the cleanest complete answer is this

const express = require('express')
const app     = express()

app.get('*', (req, res) => {
  // REDIRECT goes here
  res.redirect('https://www.YOUR_URL.com/')
})

app.set('port', (process.env.PORT || 3000))
const server = app.listen(app.get('port'), () => {})

Getting rid of all the rounded corners in Twitter Bootstrap

With SASS Bootstrap - if you are compiling Bootstrap yourself - you can set all border radius (or more specific) simply to zero:

$border-radius:               0;
$border-radius-lg:            0;
$border-radius-sm:            0;

std::wstring VS std::string

I frequently use std::string to hold utf-8 characters without any problems at all. I heartily recommend doing this when interfacing with API's which use utf-8 as the native string type as well.

For example, I use utf-8 when interfacing my code with the Tcl interpreter.

The major caveat is the length of the std::string, is no longer the number of characters in the string.

How do I call a dynamically-named method in Javascript?

you can do it like this:

function MyClass() {
    this.abc = function() {
        alert("abc");
    }
}

var myObject = new MyClass();
myObject["abc"]();

How to save a dictionary to a file?

I haven't timed it but I bet h5 is faster than pickle; the filesize with compression is almost certainly smaller.

import deepdish as dd
dd.io.save(filename, {'dict1': dict1, 'dict2': dict2}, compression=('blosc', 9))

Append an array to another array in JavaScript

If you want to modify the original array instead of returning a new array, use .push()...

array1.push.apply(array1, array2);
array1.push.apply(array1, array3);

I used .apply to push the individual members of arrays 2 and 3 at once.

or...

array1.push.apply(array1, array2.concat(array3));

To deal with large arrays, you can do this in batches.

for (var n = 0, to_add = array2.concat(array3); n < to_add.length; n+=300) {
    array1.push.apply(array1, to_add.slice(n, n+300));
}

If you do this a lot, create a method or function to handle it.

var push_apply = Function.apply.bind([].push);
var slice_call = Function.call.bind([].slice);

Object.defineProperty(Array.prototype, "pushArrayMembers", {
    value: function() {
        for (var i = 0; i < arguments.length; i++) {
            var to_add = arguments[i];
            for (var n = 0; n < to_add.length; n+=300) {
                push_apply(this, slice_call(to_add, n, n+300));
            }
        }
    }
});

and use it like this:

array1.pushArrayMembers(array2, array3);

_x000D_
_x000D_
var push_apply = Function.apply.bind([].push);_x000D_
var slice_call = Function.call.bind([].slice);_x000D_
_x000D_
Object.defineProperty(Array.prototype, "pushArrayMembers", {_x000D_
    value: function() {_x000D_
        for (var i = 0; i < arguments.length; i++) {_x000D_
            var to_add = arguments[i];_x000D_
            for (var n = 0; n < to_add.length; n+=300) {_x000D_
                push_apply(this, slice_call(to_add, n, n+300));_x000D_
            }_x000D_
        }_x000D_
    }_x000D_
});_x000D_
_x000D_
var array1 = ['a','b','c'];_x000D_
var array2 = ['d','e','f'];_x000D_
var array3 = ['g','h','i'];_x000D_
_x000D_
array1.pushArrayMembers(array2, array3);_x000D_
_x000D_
document.body.textContent = JSON.stringify(array1, null, 4);
_x000D_
_x000D_
_x000D_

JavaScript "cannot read property "bar" of undefined

Just check for it before you pass to your function. So you would pass:

thing.foo ? thing.foo.bar : undefined

Turn off deprecated errors in PHP 5.3

To only get those errors that cause the application to stop working, use:

error_reporting(E_ALL ^ (E_NOTICE | E_WARNING | E_DEPRECATED));

This will stop showing notices, warnings, and deprecated errors.

Python multiprocessing PicklingError: Can't pickle <type 'function'>

Can't pickle <type 'function'>: attribute lookup __builtin__.function failed

This error will also come if you have any inbuilt function inside the model object that was passed to the async job.

So make sure to check the model objects that are passed doesn't have inbuilt functions. (In our case we were using FieldTracker() function of django-model-utils inside the model to track a certain field). Here is the link to relevant GitHub issue.

jQuery click event not working in mobile browsers

You can use jQuery Mobile vclick event:

Normalized event for handling touchend or mouse click events on touch devices.

$(document).ready(function(){
   $('.publications').vclick(function() {
       $('#filter_wrapper').show();
   });
 });

MySQL dump by query

Combining much of above here is my real practical example, selecting records based on both meterid & timestamp. I have needed this command for years. Executes really quickly.

mysqldump -uuser -ppassword main_dbo trHourly --where="MeterID =5406 AND TIMESTAMP<'2014-10-13 05:00:00'" --no-create-info --skip-extended-insert | grep  '^INSERT' > 5406.sql

Remove legend ggplot 2.2

If your chart uses both fill and color aesthetics, you can remove the legend with:

+ guides(fill=FALSE, color=FALSE)

React JSX: selecting "selected" on selected <select> option

Use defaultValue to preselect the values for Select.

<Select defaultValue={[{ value: category.published, label: 'Publish' }]} options={statusOptions} onChange={handleStatusChange} />

How to check empty object in angular 2 template using *ngIf

You could also use something like that:

<div class="comeBack_up" *ngIf="isEmptyObject(previous_info)"  >

with the isEmptyObject method defined in your component:

isEmptyObject(obj) {
  return (obj && (Object.keys(obj).length === 0));
}

Convert a RGB Color Value to a Hexadecimal String

This is an adapted version of the answer given by Vivien Barousse with the update from Vulcan applied. In this example I use sliders to dynamically retreive the RGB values from three sliders and display that color in a rectangle. Then in method toHex() I use the values to create a color and display the respective Hex color code.

This example does not include the proper constraints for the GridBagLayout. Though the code will work, the display will look strange.

public class HexColor
{

  public static void main (String[] args)
  {
   JSlider sRed = new JSlider(0,255,1);
   JSlider sGreen = new JSlider(0,255,1);
   JSlider sBlue = new JSlider(0,255,1);
   JLabel hexCode = new JLabel();
   JPanel myPanel = new JPanel();
   GridBagLayout layout = new GridBagLayout();
   JFrame frame = new JFrame();

   //set frame to organize components using GridBagLayout 
   frame.setLayout(layout);

   //create gray filled rectangle 
   myPanel.paintComponent();
   myPanel.setBackground(Color.GRAY);

   //In practice this code is replicated and applied to sGreen and sBlue. 
   //For the sake of brevity I only show sRed in this post.
   sRed.addChangeListener(
         new ChangeListener()
         {
             @Override
             public void stateChanged(ChangeEvent e){
                 myPanel.setBackground(changeColor());
                 myPanel.repaint();
                 hexCode.setText(toHex());
         }
         }
     );
   //add each component to JFrame
   frame.add(myPanel);
   frame.add(sRed);
   frame.add(sGreen);
   frame.add(sBlue);
   frame.add(hexCode);
} //end of main

  //creates JPanel filled rectangle
  protected void paintComponent(Graphics g)
  {
      super.paintComponent(g);
      g.drawRect(360, 300, 10, 10);
      g.fillRect(360, 300, 10, 10);
  }

  //changes the display color in JPanel
  private Color changeColor()
  {
    int r = sRed.getValue();
    int b = sBlue.getValue();
    int g = sGreen.getValue();
    Color c;
    return  c = new Color(r,g,b);
  }

  //Displays hex representation of displayed color
  private String toHex()
  {
      Integer r = sRed.getValue();
      Integer g = sGreen.getValue();
      Integer b = sBlue.getValue();
      Color hC;
      hC = new Color(r,g,b);
      String hex = Integer.toHexString(hC.getRGB() & 0xffffff);
      while(hex.length() < 6){
          hex = "0" + hex;
      }
      hex = "Hex Code: #" + hex;
      return hex;
  }
}

A huge thank you to both Vivien and Vulcan. This solution works perfectly and was super simple to implement.

How can I account for period (AM/PM) using strftime?

The Python time.strftime docs say:

When used with the strptime() function, the %p directive only affects the output hour field if the %I directive is used to parse the hour.

Sure enough, changing your %H to %I makes it work.

How to type ":" ("colon") in regexp?

use \\: instead of \:.. the \ has special meaning in java strings.

Pushing from local repository to GitHub hosted remote

Subversion implicitly has the remote repository associated with it at all times. Git, on the other hand, allows many "remotes", each of which represents a single remote place you can push to or pull from.

You need to add a remote for the GitHub repository to your local repository, then use git push ${remote} or git pull ${remote} to push and pull respectively - or the GUI equivalents.

Pro Git discusses remotes here: http://git-scm.com/book/ch2-5.html

The GitHub help also discusses them in a more "task-focused" way here: http://help.github.com/remotes/

Once you have associated the two you will be able to push or pull branches.

Angular ngClass and click event for toggling class

We can also use ngClass to assign multiple CSS classes based on multiple conditions as below:

<div
  [ngClass]="{
  'class-name': trueCondition,
  'other-class': !trueCondition
}"
></div>

SEVERE: ContainerBase.addChild: start:org.apache.catalina.LifecycleException: Failed to start error

when working with spring boot the problem was that the tomcat library needs to set to provided

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-tomcat</artifactId>
    <scope>provided</scope>
</dependency>

Regex select all text between tags

You can use Pattern pattern = Pattern.compile( "[^<'tagname'/>]" );

ImportError: No module named 'MySQL'

run

pip list 

to see list of packages you have installed. If it has mysql-connector-python then that is fine.

Remember not to name your python script file as mysql.py

Visual Studio: LINK : fatal error LNK1181: cannot open input file

For me the problem was a wrong include directory. I have no idea why this caused the error with the seemingly missing lib as the include directory only contains the header files. And the library directory had the correct path set.

How to add border radius on table row

Or use box-shadow if table have collapse

Can I assume (bool)true == (int)1 for any C++ compiler?

Yes. The casts are redundant. In your expression:

true == 1

Integral promotion applies and the bool value will be promoted to an int and this promotion must yield 1.

Reference: 4.7 [conv.integral] / 4: If the source type is bool... true is converted to one.

SHA-1 fingerprint of keystore certificate

Using Google Play app signing feature & Google APIs integration in your app?

  1. If you are using Google Play App Signing, don't forget that release signing-certificate fingerprint needed for Google API credentials is not the regular upload signing keys (SHA-1) you obtain from your app by this method:

Upload signing certificate

  1. You can obtain your release SHA-1 only from App signing page of your Google Play console as shown below:-

If you use Google Play app signing, Google re-signs your app. Thats how your signing-certificate fingerprint is given by Google Play App Signing as shown below:

App Signing page - Google Play Console

Read more How to get Release SHA-1 (Signing-certificate fingerprint) if using 'Google Play app signing'

How to do a Postgresql subquery in select clause with join in from clause like SQL Server?

Complementing @Bob Jarvis and @dmikam answer, Postgres don't perform a good plan when you don't use LATERAL, below a simulation, in both cases the query data results are the same, but the cost are very different

Table structure

CREATE TABLE ITEMS (
    N INTEGER NOT NULL,
    S TEXT NOT NULL
);

INSERT INTO ITEMS
  SELECT
    (random()*1000000)::integer AS n,
    md5(random()::text) AS s
  FROM
    generate_series(1,1000000);

CREATE INDEX N_INDEX ON ITEMS(N);

Performing JOIN with GROUP BY in subquery without LATERAL

EXPLAIN 
SELECT 
    I.*
FROM ITEMS I
INNER JOIN (
    SELECT 
        COUNT(1), n
    FROM ITEMS
    GROUP BY N
) I2 ON I2.N = I.N
WHERE I.N IN (243477, 997947);

The results

Merge Join  (cost=0.87..637500.40 rows=23 width=37)
  Merge Cond: (i.n = items.n)
  ->  Index Scan using n_index on items i  (cost=0.43..101.28 rows=23 width=37)
        Index Cond: (n = ANY ('{243477,997947}'::integer[]))
  ->  GroupAggregate  (cost=0.43..626631.11 rows=861418 width=12)
        Group Key: items.n
        ->  Index Only Scan using n_index on items  (cost=0.43..593016.93 rows=10000000 width=4)

Using LATERAL

EXPLAIN 
SELECT 
    I.*
FROM ITEMS I
INNER JOIN LATERAL (
    SELECT 
        COUNT(1), n
    FROM ITEMS
    WHERE N = I.N
    GROUP BY N
) I2 ON 1=1 --I2.N = I.N
WHERE I.N IN (243477, 997947);

Results

Nested Loop  (cost=9.49..1319.97 rows=276 width=37)
  ->  Bitmap Heap Scan on items i  (cost=9.06..100.20 rows=23 width=37)
        Recheck Cond: (n = ANY ('{243477,997947}'::integer[]))
        ->  Bitmap Index Scan on n_index  (cost=0.00..9.05 rows=23 width=0)
              Index Cond: (n = ANY ('{243477,997947}'::integer[]))
  ->  GroupAggregate  (cost=0.43..52.79 rows=12 width=12)
        Group Key: items.n
        ->  Index Only Scan using n_index on items  (cost=0.43..52.64 rows=12 width=4)
              Index Cond: (n = i.n)

My Postgres version is PostgreSQL 10.3 (Debian 10.3-1.pgdg90+1)

Moving all files from one directory to another using Python

Move files with filter( using Path, os,shutil modules):

from pathlib import Path
import shutil
import os

src_path ='/media/shakil/New Volume/python/src'
trg_path ='/media/shakil/New Volume/python/trg'

for src_file in Path(src_path).glob('*.txt*'):
    shutil.move(os.path.join(src_path,src_file),trg_path)

OSError: [WinError 193] %1 is not a valid Win32 application

The file hello.py is not an executable file. You need to specify a file like python.exe

try following:

import sys
subprocess.call([sys.executable, 'hello.py', 'htmlfilename.htm'])

How to get First and Last record from a sql query?

last record :

SELECT * FROM `aboutus` order by id desc limit 1

first record :

SELECT * FROM `aboutus` order by id asc limit 1

Execute PHP function with onclick

You will have to do this via AJAX. I HEAVILY reccommend you use jQuery to make this easier for you....

$("#idOfElement").on('click', function(){

    $.ajax({
       url: 'pathToPhpFile.php',
       dataType: 'json',
       success: function(data){
            //data returned from php
       }
    });
)};

http://api.jquery.com/jQuery.ajax/

Encrypt and Decrypt text with RSA in PHP

Security warning: This code snippet is vulnerable to Bleichenbacher's 1998 padding oracle attack. See this answer for better security.

class MyEncryption
{

    public $pubkey = '...public key here...';
    public $privkey = '...private key here...';

    public function encrypt($data)
    {
        if (openssl_public_encrypt($data, $encrypted, $this->pubkey))
            $data = base64_encode($encrypted);
        else
            throw new Exception('Unable to encrypt data. Perhaps it is bigger than the key size?');

        return $data;
    }

    public function decrypt($data)
    {
        if (openssl_private_decrypt(base64_decode($data), $decrypted, $this->privkey))
            $data = $decrypted;
        else
            $data = '';

        return $data;
    }
}

Invert colors of an image in CSS or JavaScript

You can apply the style via javascript. This is the Js code below that applies the filter to the image with the ID theImage.

function invert(){
document.getElementById("theImage").style.filter="invert(100%)";
}

And this is the

<img id="theImage" class="img-responsive" src="http://i.imgur.com/1H91A5Y.png"></img>

Now all you need to do is call invert() We do this when the image is clicked.

_x000D_
_x000D_
function invert(){_x000D_
document.getElementById("theImage").style.filter="invert(100%)";_x000D_
}
_x000D_
<h4> Click image to invert </h4>_x000D_
_x000D_
<img id="theImage" class="img-responsive" src="http://i.imgur.com/1H91A5Y.png" onClick="invert()" ></img>
_x000D_
_x000D_
_x000D_

We use this on our website

Python NLTK: SyntaxError: Non-ASCII character '\xc3' in file (Sentiment Analysis -NLP)

Add the following to the top of your file # coding=utf-8

If you go to the link in the error you can seen the reason why:

Defining the Encoding

Python will default to ASCII as standard encoding if no other encoding hints are given. To define a source code encoding, a magic comment must be placed into the source files either as first or second line in the file, such as: # coding=

HTML - Display image after selecting filename

You can achieve this with the following code:

$("input").change(function(e) {

    for (var i = 0; i < e.originalEvent.srcElement.files.length; i++) {

        var file = e.originalEvent.srcElement.files[i];

        var img = document.createElement("img");
        var reader = new FileReader();
        reader.onloadend = function() {
             img.src = reader.result;
        }
        reader.readAsDataURL(file);
        $("input").after(img);
    }
});

Demo: http://jsfiddle.net/ugPDx/

How to remove a build from itunes connect?

Choose the build

The answer is that you Mouse over the icon for your build and at the end of the line you'll see a little colored minus in a circle. This removes the build and you can now click on the + sign and choose a new build for submitting.

It is an unbelievably complicated web page with tricks and gizmos to do the thing you want. I'm sure Steve never saw this page or tried to use it.

Surely it's better practice to design the screen so that you can see the options all the time, not to have the screen change depending on whether you have an app in review or not!

merge two object arrays with Angular 2 and TypeScript?

I think that you should use rather the following:

data => {
  this.results = this.results.concat(data.results);
  this._next = data.next;
},

From the concat doc:

The concat() method returns a new array comprised of the array on which it is called joined with the array(s) and/or value(s) provided as arguments.

Math functions in AngularJS bindings

While the accepted answer is right that you can inject Math to use it in angular, for this particular problem, the more conventional/angular way is the number filter:

<p>The percentage is {{(100*count/total)| number:0}}%</p>

You can read more about the number filter here: http://docs.angularjs.org/api/ng/filter/number

SyntaxError: cannot assign to operator

In case it helps someone, if your variables have hyphens in them, you may see this error since hyphens are not allowed in variable names in Python and are used as subtraction operators.

Example:

my-variable = 5   # would result in 'SyntaxError: can't assign to operator'

How can I discard remote changes and mark a file as "resolved"?

Make sure of the conflict origin: if it is the result of a git merge, see Brian Campbell's answer.

But if is the result of a git rebase, in order to discard remote (their) changes and use local changes, you would have to do a:

git checkout --theirs -- .

See "Why is the meaning of “ours” and “theirs” reversed"" to see how ours and theirs are swapped during a rebase (because the upstream branch is checked out).

List changes unexpectedly after assignment. How do I clone or copy it to prevent this?

What are the options to clone or copy a list in Python?

In Python 3, a shallow copy can be made with:

a_copy = a_list.copy()

In Python 2 and 3, you can get a shallow copy with a full slice of the original:

a_copy = a_list[:]

Explanation

There are two semantic ways to copy a list. A shallow copy creates a new list of the same objects, a deep copy creates a new list containing new equivalent objects.

Shallow list copy

A shallow copy only copies the list itself, which is a container of references to the objects in the list. If the objects contained themselves are mutable and one is changed, the change will be reflected in both lists.

There are different ways to do this in Python 2 and 3. The Python 2 ways will also work in Python 3.

Python 2

In Python 2, the idiomatic way of making a shallow copy of a list is with a complete slice of the original:

a_copy = a_list[:]

You can also accomplish the same thing by passing the list through the list constructor,

a_copy = list(a_list)

but using the constructor is less efficient:

>>> timeit
>>> l = range(20)
>>> min(timeit.repeat(lambda: l[:]))
0.30504298210144043
>>> min(timeit.repeat(lambda: list(l)))
0.40698814392089844

Python 3

In Python 3, lists get the list.copy method:

a_copy = a_list.copy()

In Python 3.5:

>>> import timeit
>>> l = list(range(20))
>>> min(timeit.repeat(lambda: l[:]))
0.38448613602668047
>>> min(timeit.repeat(lambda: list(l)))
0.6309100328944623
>>> min(timeit.repeat(lambda: l.copy()))
0.38122922903858125

Making another pointer does not make a copy

Using new_list = my_list then modifies new_list every time my_list changes. Why is this?

my_list is just a name that points to the actual list in memory. When you say new_list = my_list you're not making a copy, you're just adding another name that points at that original list in memory. We can have similar issues when we make copies of lists.

>>> l = [[], [], []]
>>> l_copy = l[:]
>>> l_copy
[[], [], []]
>>> l_copy[0].append('foo')
>>> l_copy
[['foo'], [], []]
>>> l
[['foo'], [], []]

The list is just an array of pointers to the contents, so a shallow copy just copies the pointers, and so you have two different lists, but they have the same contents. To make copies of the contents, you need a deep copy.

Deep copies

To make a deep copy of a list, in Python 2 or 3, use deepcopy in the copy module:

import copy
a_deep_copy = copy.deepcopy(a_list)

To demonstrate how this allows us to make new sub-lists:

>>> import copy
>>> l
[['foo'], [], []]
>>> l_deep_copy = copy.deepcopy(l)
>>> l_deep_copy[0].pop()
'foo'
>>> l_deep_copy
[[], [], []]
>>> l
[['foo'], [], []]

And so we see that the deep copied list is an entirely different list from the original. You could roll your own function - but don't. You're likely to create bugs you otherwise wouldn't have by using the standard library's deepcopy function.

Don't use eval

You may see this used as a way to deepcopy, but don't do it:

problematic_deep_copy = eval(repr(a_list))
  1. It's dangerous, particularly if you're evaluating something from a source you don't trust.
  2. It's not reliable, if a subelement you're copying doesn't have a representation that can be eval'd to reproduce an equivalent element.
  3. It's also less performant.

In 64 bit Python 2.7:

>>> import timeit
>>> import copy
>>> l = range(10)
>>> min(timeit.repeat(lambda: copy.deepcopy(l)))
27.55826997756958
>>> min(timeit.repeat(lambda: eval(repr(l))))
29.04534101486206

on 64 bit Python 3.5:

>>> import timeit
>>> import copy
>>> l = list(range(10))
>>> min(timeit.repeat(lambda: copy.deepcopy(l)))
16.84255409205798
>>> min(timeit.repeat(lambda: eval(repr(l))))
34.813894678023644

UnicodeEncodeError: 'ascii' codec can't encode character u'\xef' in position 0: ordinal not in range(128)

An easy solution to overcome this problem is to set your default encoding to utf8. Follow is an example

import sys

reload(sys)
sys.setdefaultencoding('utf8')

Text Progress Bar in the Console

import time,sys

for i in range(100+1):
    time.sleep(0.1)
    sys.stdout.write(('='*i)+(''*(100-i))+("\r [ %d"%i+"% ] "))
    sys.stdout.flush()

output

[ 29% ] ===================

What is lexical scope?

Lexical scope means that a function looks up variables in the context where it was defined, and not in the scope immediately around it.

Look at how lexical scope works in Lisp if you want more detail. The selected answer by Kyle Cronin in Dynamic and Lexical variables in Common Lisp is a lot clearer than the answers here.

Coincidentally I only learned about this in a Lisp class, and it happens to apply in JavaScript as well.

I ran this code in Chrome's console.

// JavaScript               Equivalent Lisp
var x = 5;                //(setf x 5)
console.debug(x);         //(print x)
function print_x(){       //(defun print-x ()
    console.debug(x);     //    (print x)
}                         //)
(function(){              //(let
    var x = 10;           //    ((x 10))
    console.debug(x);     //    (print x)
    print_x();            //    (print-x)
})();                     //)

Output:

5
10
5

POST request send json data java HttpUrlConnection

private JSONObject uploadToServer() throws IOException, JSONException {
            String query = "https://example.com";
            String json = "{\"key\":1}";

            URL url = new URL(query);
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            conn.setConnectTimeout(5000);
            conn.setRequestProperty("Content-Type", "application/json; charset=UTF-8");
            conn.setDoOutput(true);
            conn.setDoInput(true);
            conn.setRequestMethod("POST");

            OutputStream os = conn.getOutputStream();
            os.write(json.getBytes("UTF-8"));
            os.close();

            // read the response
            InputStream in = new BufferedInputStream(conn.getInputStream());
            String result = org.apache.commons.io.IOUtils.toString(in, "UTF-8");
            JSONObject jsonObject = new JSONObject(result);


            in.close();
            conn.disconnect();

            return jsonObject;
    }

How do I show a message in the foreach loop?

You are looking to see if a single value is in an array. Use in_array.

However note that case is important, as are any leading or trailing spaces. Use var_dump to find out the length of the strings too, and see if they fit.

How to pass a list from Python, by Jinja2 to JavaScript

Make some invisible HTML tags like <label>, <p>, <input> etc. and name its id, and the class name is a pattern so that you can retrieve it later.

Let you have two lists maintenance_next[] and maintenance_block_time[] of the same length, and you want to pass these two list's data to javascript using the flask. So you take some invisible label tag and set its tag name is a pattern of list's index and set its class name as value at index.

_x000D_
_x000D_
{% for i in range(maintenance_next|length): %}_x000D_
<label id="maintenance_next_{{i}}" name="{{maintenance_next[i]}}" style="display: none;"></label>_x000D_
<label id="maintenance_block_time_{{i}}" name="{{maintenance_block_time[i]}}" style="display: none;"></label>_x000D_
{% endfor%}
_x000D_
_x000D_
_x000D_

Now you can retrieve the data in javascript using some javascript operation like below -

_x000D_
_x000D_
<script>_x000D_
var total_len = {{ total_len }};_x000D_
 _x000D_
for (var i = 0; i < total_len; i++) {_x000D_
    var tm1 = document.getElementById("maintenance_next_" + i).getAttribute("name");_x000D_
    var tm2 = document.getElementById("maintenance_block_time_" + i).getAttribute("name");_x000D_
    _x000D_
    //Do what you need to do with tm1 and tm2._x000D_
    _x000D_
    console.log(tm1);_x000D_
    console.log(tm2);_x000D_
}_x000D_
</script>
_x000D_
_x000D_
_x000D_

How to make a great R reproducible example

Basically a minimal reproducible example (MWE) should enable others to exactly reproduce your issue on their machines.

A MWE consists of the following items:

  • a minimal dataset, necessary to demonstrate the problem
  • the minimal runnable code necessary to reproduce the error, which can be run on the given dataset
  • all necessary information on the used packages, the R version, and the OS it is run on.
  • in the case of random processes, a seed (set by set.seed()) for reproducibility

For examples of good MWEs, see section "Examples" at the bottom of help files on the function you are using. Simply type e.g. help(mean), or short ?mean into your R console.

Providing a minimal dataset

Usually, sharing huge data sets is not necessary and may rather discourage others from reading your question. Therefore, it is better to use built-in datasets or create a small "toy" example that resembles your original data, which is actually what is meant by minimal. If for some reason you really need to share your original data, you should use a method, such as dput(), that allows others to get an exact copy of your data.

Built-in datasets

You can use one of the built-in datasets. A comprehensive list of built-in datasets can be seen with data(). There is a short description of every data set, and more information can be obtained, e.g. with ?iris, for the 'iris' data set that comes with R. Installed packages might contain additional datasets.

Creating example data sets

Preliminary note: Sometimes you may need special formats (i.e. classes), such as factors, dates, or time series. For these, make use of functions like: as.factor, as.Date, as.xts, ... Example:

d <- as.Date("2020-12-30")

where

class(d)
# [1] "Date"

Vectors

x <- rnorm(10)  ## random vector normal distributed
x <- runif(10)  ## random vector uniformly distributed    
x <- sample(1:100, 10)  ## 10 random draws out of 1, 2, ..., 100    
x <- sample(LETTERS, 10)  ## 10 random draws out of built-in latin alphabet

Matrices

m <- matrix(1:12, 3, 4, dimnames=list(LETTERS[1:3], LETTERS[1:4]))
m
#   A B C  D
# A 1 4 7 10
# B 2 5 8 11
# C 3 6 9 12

Data frames

set.seed(42)  ## for sake of reproducibility
n <- 6
dat <- data.frame(id=1:n, 
                  date=seq.Date(as.Date("2020-12-26"), as.Date("2020-12-31"), "day"),
                  group=rep(LETTERS[1:2], n/2),
                  age=sample(18:30, n, replace=TRUE),
                  type=factor(paste("type", 1:n)),
                  x=rnorm(n))
dat
#   id       date group age   type         x
# 1  1 2020-12-26     A  27 type 1 0.0356312
# 2  2 2020-12-27     B  19 type 2 1.3149588
# 3  3 2020-12-28     A  20 type 3 0.9781675
# 4  4 2020-12-29     B  26 type 4 0.8817912
# 5  5 2020-12-30     A  26 type 5 0.4822047
# 6  6 2020-12-31     B  28 type 6 0.9657529

Note: Although it is widely used, better do not name your data frame df, because df() is an R function for the density (i.e. height of the curve at point x) of the F distribution and you might get a clash with it.

Copying original data

If you have a specific reason, or data that would be too difficult to construct an example from, you could provide a small subset of your original data, best by using dput.

Why use dput()?

dput throws all information needed to exactly reproduce your data on your console. You may simply copy the output and paste it into your question.

Calling dat (from above) produces output that still lacks information about variable classes and other features if you share it in your question. Furthermore the spaces in the type column make it difficult to do anything with it. Even when we set out to use the data, we won't manage to get important features of your data right.

  id       date group age   type         x
1  1 2020-12-26     A  27 type 1 0.0356312
2  2 2020-12-27     B  19 type 2 1.3149588
3  3 2020-12-28     A  20 type 3 0.9781675

Subset your data

Tho share a subset, use head(), subset() or the indices iris[1:4, ]. Then wrap it into dput() to give others something that can be put in R immediately. Example

dput(iris[1:4, ]) # first four rows of the iris data set

Console output to share in your question:

structure(list(Sepal.Length = c(5.1, 4.9, 4.7, 4.6), Sepal.Width = c(3.5, 
3, 3.2, 3.1), Petal.Length = c(1.4, 1.4, 1.3, 1.5), Petal.Width = c(0.2, 
0.2, 0.2, 0.2), Species = structure(c(1L, 1L, 1L, 1L), .Label = c("setosa", 
"versicolor", "virginica"), class = "factor")), row.names = c(NA, 
4L), class = "data.frame")

When using dput, you may also want to include only relevant columns, e.g. dput(mtcars[1:3, c(2, 5, 6)])

Note: If your data frame has a factor with many levels, the dput output can be unwieldy because it will still list all the possible factor levels even if they aren't present in the the subset of your data. To solve this issue, you can use the droplevels() function. Notice below how species is a factor with only one level, e.g. dput(droplevels(iris[1:4, ])). One other caveat for dput is that it will not work for keyed data.table objects or for grouped tbl_df (class grouped_df) from the tidyverse. In these cases you can convert back to a regular data frame before sharing, dput(as.data.frame(my_data)).

Producing minimal code

Combined with the minimal data (see above), your code should exactly reproduce the problem on another machine by simply copying and pasting it.

This should be the easy part but often isn't. What you should not do:

  • showing all kinds of data conversions; make sure the provided data is already in the correct format (unless that is the problem, of course)
  • copy-paste a whole script that gives an error somewhere. Try to locate which lines exactly result in the error. More often than not, you'll find out what the problem is yourself.

What you should do:

  • add which packages you use if you use any (using library())
  • test run your code in a fresh R session to ensure the code is runnable. People should be able to copy-paste your data and your code in the console and get the same as you have.
  • if you open connections or create files, add some code to close them or delete the files (using unlink())
  • if you change options, make sure the code contains a statement to revert them back to the original ones. (eg op <- par(mfrow=c(1,2)) ...some code... par(op) )

Providing necessary information

In most cases, just the R version and the operating system will suffice. When conflicts arise with packages, giving the output of sessionInfo() can really help. When talking about connections to other applications (be it through ODBC or anything else), one should also provide version numbers for those, and if possible, also the necessary information on the setup.

If you are running R in R Studio, using rstudioapi::versionInfo() can help report your RStudio version.

If you have a problem with a specific package, you may want to provide the package version by giving the output of packageVersion("name of the package").

Seed

Using set.seed() you may specify a seed1, i.e. the specific state, R's random number generator is fixed. This makes it possible for random functions, such as sample(), rnorm(), runif() and lots of others, to always return the same result, Example:

set.seed(42)
rnorm(3)
# [1]  1.3709584 -0.5646982  0.3631284

set.seed(42)
rnorm(3)
# [1]  1.3709584 -0.5646982  0.3631284

1 Note: The output of set.seed() differs between R >3.6.0 and previous versions. Specify which R version you used for the random process, and don't be surprised if you get slightly different results when following old questions. To get the same result in such cases, you can use the RNGversion()-function before set.seed() (e.g.: RNGversion("3.5.2")).

Yii2 data provider default sorting

Try to this one

$dataProvider = new ActiveDataProvider([
    'query' => $query,
]);

$sort = $dataProvider->getSort();

$sort->defaultOrder = ['id' => SORT_ASC];

$dataProvider->setSort($sort);

Easiest way to use SVG in Android?

1)Right Click On drawable directory then go to new then go to vector assets 2)change asset type from clip art to local 3)browse your file 4)give size 5)then click next then done Your usable svg will be generated in drawable directory

How to convert decimal to hexadecimal in JavaScript

var number = 3200;
var hexString = number.toString(16);

The 16 is the radix and there are 16 values in a hexadecimal number :-)

OrderBy descending in Lambda expression?

Try this:

List<int> list = new List<int>();
list.Add(1);
list.Add(5);
list.Add(4);
list.Add(3);
list.Add(2);

foreach (var item in list.OrderByDescending(x => x))
{
    Console.WriteLine(item);                
}

Swift: declare an empty dictionary

I'm usually using

var dictionary:[String:String] = [:]
dictionary.removeAll()

Run Command Line & Command From VBS

Set oShell = CreateObject ("WScript.Shell") 
oShell.run "cmd.exe /C copy ""S:Claims\Sound.wav"" ""C:\WINDOWS\Media\Sound.wav"" "

What is the Java equivalent of PHP var_dump?

Your alternatives are to override the toString() method of your object to output its contents in a way that you like, or to use reflection to inspect the object (in a way similar to what debuggers do).

The advantage of using reflection is that you won't need to modify your individual objects to be "analysable", but there is added complexity and if you need nested object support you'll have to write that.

This code will list the fields and their values for an Object "o"

Field[] fields = o.getClass().getDeclaredFields();
for (int i=0; i<fields.length; i++)
{
    System.out.println(fields[i].getName() + " - " + fields[i].get(o));
}

How to read until EOF from cin in C++

You can do it without explicit loops by using stream iterators. I'm sure that it uses some kind of loop internally.

#include <string>
#include <iostream>
#include <istream>
#include <ostream>
#include <iterator>

int main()
{
// don't skip the whitespace while reading
  std::cin >> std::noskipws;

// use stream iterators to copy the stream to a string
  std::istream_iterator<char> it(std::cin);
  std::istream_iterator<char> end;
  std::string results(it, end);

  std::cout << results;
}

JQuery addclass to selected div, remove class if another div is selected

**This can be achived easily using two different ways:**

1)We can also do this by using addClass and removeClass of Jquery
2)Toggle class of jQuery

**1)First Way**

$(documnet.ready(function(){
$('#dvId').click(function(){
  $('#dvId').removeClass('active class or your class name which you want to    remove').addClass('active class or your class name which you want to add');     
});
});

**2) Second Way**

i) Here we need to add the class which we want to show while page get loads.
ii)after clicking on div we we will toggle class i.e. the class is added while loading page gets removed and class which we provide in toggleClss gets added :)

<div id="dvId" class="ActiveClassname ">
</div

$(documnet.ready(function(){
$('#dvId').click(function(){
  $('#dvId').toggleClass('ActiveClassname InActiveClassName');     
});
});


Enjoy.....:)

If you any doubt free to ask any time...

Update statement using with clause

The WITH syntax appears to be valid in an inline view, e.g.

UPDATE (WITH comp AS ...
        SELECT SomeColumn, ComputedValue FROM t INNER JOIN comp ...)
   SET SomeColumn=ComputedValue;

But in the quick tests I did this always failed with ORA-01732: data manipulation operation not legal on this view, although it succeeded if I rewrote to eliminate the WITH clause. So the refactoring may interfere with Oracle's ability to guarantee key-preservation.

You should be able to use a MERGE, though. Using the simple example you've posted this doesn't even require a WITH clause:

MERGE INTO mytable t
USING (select *, 42 as ComputedValue from mytable where id = 1) comp
ON (t.id = comp.id)
WHEN MATCHED THEN UPDATE SET SomeColumn=ComputedValue;

But I understand you have a more complex subquery you want to factor out. I think that you will be able to make the subquery in the USING clause arbitrarily complex, incorporating multiple WITH clauses.

How to access at request attributes in JSP?

Using JSTL:

<c:set var="message" value='${requestScope["Error_Message"]}' />

Here var sets the variable name and request.getAttribute is equal to requestScope. But it's not essential. ${Error_Message} will give you the same outcome. It'll search every scope. If you want to do some operation with content you take from Error_Message you have to do it using message. like below one.

<c:out value="${message}"/>

How to get disk capacity and free space of remote computer

Just one command simple sweet and clean but this only works for local disks

Get-PSDrive

enter image description here

You could still use this command on a remote server by doing a Enter-PSSession -Computername ServerName and then run the Get-PSDrive it will pull the data as if you ran it from the server.

How to use BOOLEAN type in SELECT statement

Compile this in your database and start using boolean statements in your querys.

note: the function get's a varchar2 param, so be sure to wrap any "strings" in your statement. It will return 1 for true and 0 for false;

select bool('''abc''<''bfg''') from dual;

CREATE OR REPLACE function bool(p_str in varchar2) return varchar2 
 is
 begin

 execute immediate ' begin if '||P_str||' then
          :v_res :=  1;
       else
          :v_res :=  0;
       end if; end;' using out v_res;

       return v_res;

 exception 
  when others then 
    return '"'||p_str||'" is not a boolean expr.';
 end;
/

Should I use != or <> for not equal in T-SQL?

One alternative would be to use the NULLIF operator other than <> or != which returns NULL if the two arguments are equal NULLIF in Microsoft Docs. So I believe WHERE clause can be modified for <> and != as follows:

NULLIF(arg1, arg2) IS NOT NULL

As I found that, using <> and != doesn't work for date in some cases. Hence using the above expression does the needful.

Superscript in Python plots

If you want to write unit per meter (m^-1), use $m^{-1}$), which means -1 inbetween {}

Example: plt.ylabel("Specific Storage Values ($m^{-1}$)", fontsize = 12 )

Inserting data into a MySQL table using VB.NET

your str_carSql should be exactly like this:

str_carSql = "insert into members_car (car_id, member_id, model, color, chassis_id, plate_number, code) values (@id,@m_id,@model,@color,@ch_id,@pt_num,@code)"

Good Luck

SQL Server Linked Server Example Query

For what it's worth, I found the following syntax to work the best:

SELECT * FROM [LINKED_SERVER]...[TABLE]

I couldn't get the recommendations of others to work, using the database name. Additionally, this data source has no schema.

Is there a Public FTP server to test upload and download?

Try ftp://test.rebex.net/

It is read-only used for testing Rebex components to list directory and download. Allows also to test FTP/SSL and IMAP.

Username is "demo", password is "password"

See https://test.rebex.net/ for more information.

Get the difference between two dates both In Months and days in sql

Updated for correctness. Originally answered by @jen.

with DATES as (
   select TO_DATE('20120101', 'YYYYMMDD') as Date1,
          TO_DATE('20120325', 'YYYYMMDD') as Date2
   from DUAL union all
   select TO_DATE('20120101', 'YYYYMMDD') as Date1,
          TO_DATE('20130101', 'YYYYMMDD') as Date2
   from DUAL union all
   select TO_DATE('20120101', 'YYYYMMDD') as Date1,
          TO_DATE('20120101', 'YYYYMMDD') as Date2
   from DUAL union all
   select TO_DATE('20130228', 'YYYYMMDD') as Date1,
          TO_DATE('20130301', 'YYYYMMDD') as Date2
   from DUAL union all
   select TO_DATE('20130228', 'YYYYMMDD') as Date1,
          TO_DATE('20130401', 'YYYYMMDD') as Date2
   from DUAL
), MONTHS_BTW as (
   select Date1, Date2,
          MONTHS_BETWEEN(Date2, Date1) as NumOfMonths
   from DATES
)
select TO_CHAR(Date1, 'MON DD YYYY') as Date_1,
       TO_CHAR(Date2, 'MON DD YYYY') as Date_2,
       NumOfMonths as Num_Of_Months,
       TRUNC(NumOfMonths) as "Month(s)",
       ADD_MONTHS(Date2, - TRUNC(NumOfMonths)) - Date1 as "Day(s)"
from MONTHS_BTW;

SQLFiddle Demo :

    +--------------+--------------+-----------------+-----------+--------+
    |   DATE_1     |   DATE_2     | NUM_OF_MONTHS   | MONTH(S)  | DAY(S) |
    +--------------+--------------+-----------------+-----------+--------+
    | JAN 01 2012  | MAR 25 2012  | 2.774193548387  |        2  |     24 |
    | JAN 01 2012  | JAN 01 2013  | 12              |       12  |      0 |
    | JAN 01 2012  | JAN 01 2012  | 0               |        0  |      0 |
    | FEB 28 2013  | MAR 01 2013  | 0.129032258065  |        0  |      1 |
    | FEB 28 2013  | APR 01 2013  | 1.129032258065  |        1  |      1 |
    +--------------+--------------+-----------------+-----------+--------+

Notice, how for the last two dates, Oracle reports the decimal part of months (which gives days) incorrectly. 0.1290 corresponds to exactly 4 days with Oracle considering 31 days in a month (for both March and April).

Check if a file exists locally using JavaScript only

Fortunately, it's not possible (for security reasons) to access client-side filesystem with standard JS. Some proprietary solutions exist though (like Microsoft's IE-only ActiveX component).

UnicodeEncodeError: 'latin-1' codec can't encode character

SQLAlchemy users can simply specify their field as convert_unicode=True.

Example: sqlalchemy.String(1000, convert_unicode=True)

SQLAlchemy will simply accept unicode objects and return them back, handling the encoding itself.

Docs

Freezing Row 1 and Column A at the same time

Select cell B2 and click "Freeze Panes" this will freeze Row 1 and Column A.

For future reference, selecting Freeze Panes in Excel will freeze the rows above your selected cell and the columns to the left of your selected cell. For example, to freeze rows 1 and 2 and column A, you could select cell B3 and click Freeze Panes. You could also freeze columns A and B and row 1, by selecting cell C2 and clicking "Freeze Panes".

Visual Aid on Freeze Panes in Excel 2010 - http://www.dummies.com/how-to/content/how-to-freeze-panes-in-an-excel-2010-worksheet.html

Microsoft Reference Guide (More Complicated, but resourceful none the less) - http://office.microsoft.com/en-us/excel-help/freeze-or-lock-rows-and-columns-HP010342542.aspx

Config Error: This configuration section cannot be used at this path

I noticed one answer that was similar, but in my case I used the IIS Configured Editor to find the section I wanted to "unlock".

enter image description here

enter image description here

Then I copied the path and used it in my automation to unlock it prior to changing the sections I wanted to edit.

. "$($env:windir)\system32\inetsrv\appcmd" unlock config -section:system.webServer/security/authentication/windowsAuthentication
. "$($env:windir)\system32\inetsrv\appcmd" unlock config -section:system.webServer/security/authentication/anonymousAuthentication

What is the 'pythonic' equivalent to the 'fold' function from functional programming?

Haskell

foldl (+) 0 [1,2,3,4,5]

Python

reduce(lambda a,b: a+b, [1,2,3,4,5], 0)

Obviously, that is a trivial example to illustrate a point. In Python you would just do sum([1,2,3,4,5]) and even Haskell purists would generally prefer sum [1,2,3,4,5].

For non-trivial scenarios when there is no obvious convenience function, the idiomatic pythonic approach is to explicitly write out the for loop and use mutable variable assignment instead of using reduce or a fold.

That is not at all the functional style, but that is the "pythonic" way. Python is not designed for functional purists. See how Python favors exceptions for flow control to see how non-functional idiomatic python is.

Why when a constructor is annotated with @JsonCreator, its arguments must be annotated with @JsonProperty?

As precised in the annotation documentation, the annotation indicates that the argument name is used as the property name without any modifications, but it can be specified to non-empty value to specify different name:

How to generate components in a specific folder with Angular CLI?

Use 'ng generate component ./target_directory/Component_Name'

How does one Display a Hyperlink in React Native App?

You can use linking property <Text style={{color: 'skyblue'}} onPress={() => Linking.openURL('http://yahoo.com')}> Yahoo

Convert a string to a datetime

Try converting date like this:

    Dim expenddt as Date = Date.ParseExact(edate, "dd/mm/yyyy", 
System.Globalization.DateTimeFormatInfo.InvariantInfo);

Hope this helps.

Finding current executable's path without /proc/self/exe

The use of /proc/self/exe is non-portable and unreliable. On my Ubuntu 12.04 system, you must be root to read/follow the symlink. This will make the Boost example and probably the whereami() solutions posted fail.

This post is very long but discusses the actual issues and presents code which actually works along with validation against a test suite.

The best way to find your program is to retrace the same steps the system uses. This is done by using argv[0] resolved against file system root, pwd, path environment and considering symlinks, and pathname canonicalization. This is from memory but I have done this in the past successfully and tested it in a variety of different situations. It is not guaranteed to work, but if it doesn't you probably have much bigger problems and it is more reliable overall than any of the other methods discussed. There are situations on a Unix compatible system in which proper handling of argv[0] will not get you to your program but then you are executing in a certifiably broken environment. It is also fairly portable to all Unix derived systems since around 1970 and even some non-Unix derived systems as it basically relies on libc() standard functionality and standard command line functionality. It should work on Linux (all versions), Android, Chrome OS, Minix, original Bell Labs Unix, FreeBSD, NetBSD, OpenBSD, BSD x.x, SunOS, Solaris, SYSV, HP-UX, Concentrix, SCO, Darwin, AIX, OS X, NeXTSTEP, etc. And with a little modification probably VMS, VM/CMS, DOS/Windows, ReactOS, OS/2, etc. If a program was launched directly from a GUI environment, it should have set argv[0] to an absolute path.

Understand that almost every shell on every Unix compatible operating system that has ever been released basically finds programs the same way and sets up the operating environment almost the same way (with some optional extras). And any other program that launches a program is expected to create the same environment (argv, environment strings, etc.) for that program as if it were run from a shell, with some optional extras. A program or user can setup an environment that deviates from this convention for other subordinate programs that it launches but if it does, this is a bug and the program has no reasonable expectation that the subordinate program or its subordinates will function correctly.

Possible values of argv[0] include:

  • /path/to/executable — absolute path
  • ../bin/executable — relative to pwd
  • bin/executable — relative to pwd
  • ./foo — relative to pwd
  • executable — basename, find in path
  • bin//executable — relative to pwd, non-canonical
  • src/../bin/executable — relative to pwd, non-canonical, backtracking
  • bin/./echoargc — relative to pwd, non-canonical

Values you should not see:

  • ~/bin/executable — rewritten before your program runs.
  • ~user/bin/executable — rewritten before your program runs
  • alias — rewritten before your program runs
  • $shellvariable — rewritten before your program runs
  • *foo* — wildcard, rewritten before your program runs, not very useful
  • ?foo? — wildcard, rewritten before your program runs, not very useful

In addition, these may contain non-canonical path names and multiple layers of symbolic links. In some cases, there may be multiple hard links to the same program. For example, /bin/ls, /bin/ps, /bin/chmod, /bin/rm, etc. may be hard links to /bin/busybox.

To find yourself, follow the steps below:

  • Save pwd, PATH, and argv[0] on entry to your program (or initialization of your library) as they may change later.

  • Optional: particularly for non-Unix systems, separate out but don't discard the pathname host/user/drive prefix part, if present; the part which often precedes a colon or follows an initial "//".

  • If argv[0] is an absolute path, use that as a starting point. An absolute path probably starts with "/" but on some non-Unix systems it might start with "" or a drive letter or name prefix followed by a colon.

  • Else if argv[0] is a relative path (contains "/" or "" but doesn't start with it, such as "../../bin/foo", then combine pwd+"/"+argv[0] (use present working directory from when program started, not current).

  • Else if argv[0] is a plain basename (no slashes), then combine it with each entry in PATH environment variable in turn and try those and use the first one which succeeds.

  • Optional: Else try the very platform specific /proc/self/exe, /proc/curproc/file (BSD), and (char *)getauxval(AT_EXECFN), and dlgetname(...) if present. You might even try these before argv[0]-based methods, if they are available and you don't encounter permission issues. In the somewhat unlikely event (when you consider all versions of all systems) that they are present and don't fail, they might be more authoritative.

  • Optional: check for a path name passed in using a command line parameter.

  • Optional: check for a pathname in the environment explicitly passed in by your wrapper script, if any.

  • Optional: As a last resort try environment variable "_". It might point to a different program entirely, such as the users shell.

  • Resolve symlinks, there may be multiple layers. There is the possibility of infinite loops, though if they exist your program probably won't get invoked.

  • Canonicalize filename by resolving substrings like "/foo/../bar/" to "/bar/". Note this may potentially change the meaning if you cross a network mount point, so canonization is not always a good thing. On a network server, ".." in symlink may be used to traverse a path to another file in the server context instead of on the client. In this case, you probably want the client context so canonicalization is ok. Also convert patterns like "/./" to "/" and "//" to "/". In shell, readlink --canonicalize will resolve multiple symlinks and canonicalize name. Chase may do similar but isn't installed. realpath() or canonicalize_file_name(), if present, may help.

If realpath() doesn't exist at compile time, you might borrow a copy from a permissively licensed library distribution, and compile it in yourself rather than reinventing the wheel. Fix the potential buffer overflow (pass in sizeof output buffer, think strncpy() vs strcpy()) if you will be using a buffer less than PATH_MAX. It may be easier just to use a renamed private copy rather than testing if it exists. Permissive license copy from android/darwin/bsd: https://android.googlesource.com/platform/bionic/+/f077784/libc/upstream-freebsd/lib/libc/stdlib/realpath.c

Be aware that multiple attempts may be successful or partially successful and they might not all point to the same executable, so consider verifying your executable; however, you may not have read permission — if you can't read it, don't treat that as a failure. Or verify something in proximity to your executable such as the "../lib/" directory you are trying to find. You may have multiple versions, packaged and locally compiled versions, local and network versions, and local and USB-drive portable versions, etc. and there is a small possibility that you might get two incompatible results from different methods of locating. And "_" may simply point to the wrong program.

A program using execve can deliberately set argv[0] to be incompatible with the actual path used to load the program and corrupt PATH, "_", pwd, etc. though there isn't generally much reason to do so; but this could have security implications if you have vulnerable code that ignores the fact that your execution environment can be changed in variety of ways including, but not limited, to this one (chroot, fuse filesystem, hard links, etc.) It is possible for shell commands to set PATH but fail to export it.

You don't necessarily need to code for non-Unix systems but it would be a good idea to be aware of some of the peculiarities so you can write the code in such a way that it isn't as hard for someone to port later. Be aware that some systems (DEC VMS, DOS, URLs, etc.) might have drive names or other prefixes which end with a colon such as "C:", "sys$drive:[foo]bar", and "file:///foo/bar/baz". Old DEC VMS systems use "[" and "]" to enclose the directory portion of the path though this may have changed if your program is compiled in a POSIX environment. Some systems, such as VMS, may have a file version (separated by a semicolon at the end). Some systems use two consecutive slashes as in "//drive/path/to/file" or "user@host:/path/to/file" (scp command) or "file://hostname/path/to/file" (URL). In some cases (DOS and Windows), PATH might have different separator characters — ";" vs ":" and "" vs "/" for a path separator. In csh/tsh there is "path" (delimited with spaces) and "PATH" delimited with colons but your program should receive PATH so you don't need to worry about path. DOS and some other systems can have relative paths that start with a drive prefix. C:foo.exe refers to foo.exe in the current directory on drive C, so you do need to lookup current directory on C: and use that for pwd.

An example of symlinks and wrappers on my system:

/usr/bin/google-chrome is symlink to
/etc/alternatives/google-chrome  which is symlink to
/usr/bin/google-chrome-stable which is symlink to
/opt/google/chrome/google-chrome which is a bash script which runs
/opt/google/chome/chrome

Note that user bill posted a link above to a program at HP that handles the three basic cases of argv[0]. It needs some changes, though:

  • It will be necessary to rewrite all the strcat() and strcpy() to use strncat() and strncpy(). Even though the variables are declared of length PATHMAX, an input value of length PATHMAX-1 plus the length of concatenated strings is > PATHMAX and an input value of length PATHMAX would be unterminated.
  • It needs to be rewritten as a library function, rather than just to print out results.
  • It fails to canonicalize names (use the realpath code I linked to above)
  • It fails to resolve symbolic links (use the realpath code)

So, if you combine both the HP code and the realpath code and fix both to be resistant to buffer overflows, then you should have something which can properly interpret argv[0].

The following illustrates actual values of argv[0] for various ways of invoking the same program on Ubuntu 12.04. And yes, the program was accidentally named echoargc instead of echoargv. This was done using a script for clean copying but doing it manually in shell gets same results (except aliases don't work in script unless you explicitly enable them).

cat ~/src/echoargc.c
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
main(int argc, char **argv)
{
  printf("  argv[0]=\"%s\"\n", argv[0]);
  sleep(1);  /* in case run from desktop */
}
tcc -o ~/bin/echoargc ~/src/echoargc.c
cd ~
/home/whitis/bin/echoargc
  argv[0]="/home/whitis/bin/echoargc"
echoargc
  argv[0]="echoargc"
bin/echoargc
  argv[0]="bin/echoargc"
bin//echoargc
  argv[0]="bin//echoargc"
bin/./echoargc
  argv[0]="bin/./echoargc"
src/../bin/echoargc
  argv[0]="src/../bin/echoargc"
cd ~/bin
*echo*
  argv[0]="echoargc"
e?hoargc
  argv[0]="echoargc"
./echoargc
  argv[0]="./echoargc"
cd ~/src
../bin/echoargc
  argv[0]="../bin/echoargc"
cd ~/junk
~/bin/echoargc
  argv[0]="/home/whitis/bin/echoargc"
~whitis/bin/echoargc
  argv[0]="/home/whitis/bin/echoargc"
alias echoit=~/bin/echoargc
echoit
  argv[0]="/home/whitis/bin/echoargc"
echoarg=~/bin/echoargc
$echoarg
  argv[0]="/home/whitis/bin/echoargc"
ln -s ~/bin/echoargc junk1
./junk1
  argv[0]="./junk1"
ln -s /home/whitis/bin/echoargc junk2
./junk2
  argv[0]="./junk2"
ln -s junk1 junk3
./junk3
  argv[0]="./junk3"


gnome-desktop-item-edit --create-new ~/Desktop
# interactive, create desktop link, then click on it
  argv[0]="/home/whitis/bin/echoargc"
# interactive, right click on gnome application menu, pick edit menus
# add menu item for echoargc, then run it from gnome menu
 argv[0]="/home/whitis/bin/echoargc"

 cat ./testargcscript 2>&1 | sed -e 's/^/    /g'
#!/bin/bash
# echoargc is in ~/bin/echoargc
# bin is in path
shopt -s expand_aliases
set -v
cat ~/src/echoargc.c
tcc -o ~/bin/echoargc ~/src/echoargc.c
cd ~
/home/whitis/bin/echoargc
echoargc
bin/echoargc
bin//echoargc
bin/./echoargc
src/../bin/echoargc
cd ~/bin
*echo*
e?hoargc
./echoargc
cd ~/src
../bin/echoargc
cd ~/junk
~/bin/echoargc
~whitis/bin/echoargc
alias echoit=~/bin/echoargc
echoit
echoarg=~/bin/echoargc
$echoarg
ln -s ~/bin/echoargc junk1
./junk1
ln -s /home/whitis/bin/echoargc junk2
./junk2
ln -s junk1 junk3
./junk3

These examples illustrate that the techniques described in this post should work in a wide range of circumstances and why some of the steps are necessary.

EDIT: Now, the program that prints argv[0] has been updated to actually find itself.

// Copyright 2015 by Mark Whitis.  License=MIT style
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <limits.h>
#include <assert.h>
#include <string.h>
#include <errno.h>

// "look deep into yourself, Clarice"  -- Hanibal Lector
char findyourself_save_pwd[PATH_MAX];
char findyourself_save_argv0[PATH_MAX];
char findyourself_save_path[PATH_MAX];
char findyourself_path_separator='/';
char findyourself_path_separator_as_string[2]="/";
char findyourself_path_list_separator[8]=":";  // could be ":; "
char findyourself_debug=0;

int findyourself_initialized=0;

void findyourself_init(char *argv0)
{

  getcwd(findyourself_save_pwd, sizeof(findyourself_save_pwd));

  strncpy(findyourself_save_argv0, argv0, sizeof(findyourself_save_argv0));
  findyourself_save_argv0[sizeof(findyourself_save_argv0)-1]=0;

  strncpy(findyourself_save_path, getenv("PATH"), sizeof(findyourself_save_path));
  findyourself_save_path[sizeof(findyourself_save_path)-1]=0;
  findyourself_initialized=1;
}


int find_yourself(char *result, size_t size_of_result)
{
  char newpath[PATH_MAX+256];
  char newpath2[PATH_MAX+256];

  assert(findyourself_initialized);
  result[0]=0;

  if(findyourself_save_argv0[0]==findyourself_path_separator) {
    if(findyourself_debug) printf("  absolute path\n");
     realpath(findyourself_save_argv0, newpath);
     if(findyourself_debug) printf("  newpath=\"%s\"\n", newpath);
     if(!access(newpath, F_OK)) {
        strncpy(result, newpath, size_of_result);
        result[size_of_result-1]=0;
        return(0);
     } else {
    perror("access failed 1");
      }
  } else if( strchr(findyourself_save_argv0, findyourself_path_separator )) {
    if(findyourself_debug) printf("  relative path to pwd\n");
    strncpy(newpath2, findyourself_save_pwd, sizeof(newpath2));
    newpath2[sizeof(newpath2)-1]=0;
    strncat(newpath2, findyourself_path_separator_as_string, sizeof(newpath2));
    newpath2[sizeof(newpath2)-1]=0;
    strncat(newpath2, findyourself_save_argv0, sizeof(newpath2));
    newpath2[sizeof(newpath2)-1]=0;
    realpath(newpath2, newpath);
    if(findyourself_debug) printf("  newpath=\"%s\"\n", newpath);
    if(!access(newpath, F_OK)) {
        strncpy(result, newpath, size_of_result);
        result[size_of_result-1]=0;
        return(0);
     } else {
    perror("access failed 2");
      }
  } else {
    if(findyourself_debug) printf("  searching $PATH\n");
    char *saveptr;
    char *pathitem;
    for(pathitem=strtok_r(findyourself_save_path, findyourself_path_list_separator,  &saveptr); pathitem; pathitem=strtok_r(NULL, findyourself_path_list_separator, &saveptr) ) {
       if(findyourself_debug>=2) printf("pathitem=\"%s\"\n", pathitem);
       strncpy(newpath2, pathitem, sizeof(newpath2));
       newpath2[sizeof(newpath2)-1]=0;
       strncat(newpath2, findyourself_path_separator_as_string, sizeof(newpath2));
       newpath2[sizeof(newpath2)-1]=0;
       strncat(newpath2, findyourself_save_argv0, sizeof(newpath2));
       newpath2[sizeof(newpath2)-1]=0;
       realpath(newpath2, newpath);
       if(findyourself_debug) printf("  newpath=\"%s\"\n", newpath);
      if(!access(newpath, F_OK)) {
          strncpy(result, newpath, size_of_result);
          result[size_of_result-1]=0;
          return(0);
      }
    } // end for
    perror("access failed 3");

  } // end else
  // if we get here, we have tried all three methods on argv[0] and still haven't succeeded.   Include fallback methods here.
  return(1);
}

main(int argc, char **argv)
{
  findyourself_init(argv[0]);

  char newpath[PATH_MAX];
  printf("  argv[0]=\"%s\"\n", argv[0]);
  realpath(argv[0], newpath);
  if(strcmp(argv[0],newpath)) { printf("  realpath=\"%s\"\n", newpath); }
  find_yourself(newpath, sizeof(newpath));
  if(1 || strcmp(argv[0],newpath)) { printf("  findyourself=\"%s\"\n", newpath); }
  sleep(1);  /* in case run from desktop */
}

And here is the output which demonstrates that in every one of the previous tests it actually did find itself.

tcc -o ~/bin/echoargc ~/src/echoargc.c
cd ~
/home/whitis/bin/echoargc
  argv[0]="/home/whitis/bin/echoargc"
  findyourself="/home/whitis/bin/echoargc"
echoargc
  argv[0]="echoargc"
  realpath="/home/whitis/echoargc"
  findyourself="/home/whitis/bin/echoargc"
bin/echoargc
  argv[0]="bin/echoargc"
  realpath="/home/whitis/bin/echoargc"
  findyourself="/home/whitis/bin/echoargc"
bin//echoargc
  argv[0]="bin//echoargc"
  realpath="/home/whitis/bin/echoargc"
  findyourself="/home/whitis/bin/echoargc"
bin/./echoargc
  argv[0]="bin/./echoargc"
  realpath="/home/whitis/bin/echoargc"
  findyourself="/home/whitis/bin/echoargc"
src/../bin/echoargc
  argv[0]="src/../bin/echoargc"
  realpath="/home/whitis/bin/echoargc"
  findyourself="/home/whitis/bin/echoargc"
cd ~/bin
*echo*
  argv[0]="echoargc"
  realpath="/home/whitis/bin/echoargc"
  findyourself="/home/whitis/bin/echoargc"
e?hoargc
  argv[0]="echoargc"
  realpath="/home/whitis/bin/echoargc"
  findyourself="/home/whitis/bin/echoargc"
./echoargc
  argv[0]="./echoargc"
  realpath="/home/whitis/bin/echoargc"
  findyourself="/home/whitis/bin/echoargc"
cd ~/src
../bin/echoargc
  argv[0]="../bin/echoargc"
  realpath="/home/whitis/bin/echoargc"
  findyourself="/home/whitis/bin/echoargc"
cd ~/junk
~/bin/echoargc
  argv[0]="/home/whitis/bin/echoargc"
  findyourself="/home/whitis/bin/echoargc"
~whitis/bin/echoargc
  argv[0]="/home/whitis/bin/echoargc"
  findyourself="/home/whitis/bin/echoargc"
alias echoit=~/bin/echoargc
echoit
  argv[0]="/home/whitis/bin/echoargc"
  findyourself="/home/whitis/bin/echoargc"
echoarg=~/bin/echoargc
$echoarg
  argv[0]="/home/whitis/bin/echoargc"
  findyourself="/home/whitis/bin/echoargc"
rm junk1 junk2 junk3
ln -s ~/bin/echoargc junk1
./junk1
  argv[0]="./junk1"
  realpath="/home/whitis/bin/echoargc"
  findyourself="/home/whitis/bin/echoargc"
ln -s /home/whitis/bin/echoargc junk2
./junk2
  argv[0]="./junk2"
  realpath="/home/whitis/bin/echoargc"
  findyourself="/home/whitis/bin/echoargc"
ln -s junk1 junk3
./junk3
  argv[0]="./junk3"
  realpath="/home/whitis/bin/echoargc"
  findyourself="/home/whitis/bin/echoargc"

The two GUI launches described above also correctly find the program.

There is one potential pitfall. The access() function drops permissions if the program is setuid before testing. If there is a situation where the program can be found as an elevated user but not as a regular user, then there might be a situation where these tests would fail, although it is unlikely the program could actually be executed under those circumstances. One could use euidaccess() instead. It is possible, however, that it might find an inaccessable program earlier on path than the actual user could.

Task<> does not contain a definition for 'GetAwaiter'

In my case just add using System; solve the issue.

Comparing two strings, ignoring case in C#

The .ToLowerCase version is not going to be faster - it involves an extra string allocation (which must later be collected), etc.

Personally, I'd use

string.Equals(val, "astringvalue",  StringComparison.OrdinalIgnoreCase)

this avoids all the issues of culture-sensitive strings, but as a consequence it avoids all the issues of culture-sensitive strings. Only you know whether that is OK in your context.

Using the string.Equals static method avoids any issues with val being null.

Regular expression for exact match of a string

(?<![\w\d])abc(?![\w\d])

this makes sure that your match is not preceded by some character, number, or underscore and is not followed immediately by character or number, or underscore

so it will match "abc" in "abc", "abc.", "abc ", but not "4abc", nor "abcde"

Can I install/update WordPress plugins without providing FTP access?

Just a quick change to wp-config.php

define('FS_METHOD','direct');

That’s it, enjoy your wordpress updates without ftp!

Alternate Method:

There are hosts out there that will prevent this method from working to ease your WordPress updating. Fortunately, there is another way to keep this pest from prompting you for your FTP user name and password.

Again, after the MYSQL login declarations in your wp-config.php file, add the following:

define("FTP_HOST", "localhost");
define("FTP_USER", "yourftpusername");
define("FTP_PASS", "yourftppassword");

What does /p mean in set /p?

For future reference, you can get help for any command by using the /? switch, which should explain what switches do what.

According to the set /? screen, the format for set /p is SET /P variable=[promptString] which would indicate that the p in /p is "prompt." It just prints in your example because <nul passes in a nul character which immediately ends the prompt so it just acts like it's printing. It's still technically prompting for input, it's just immediately receiving it.

/L in for /L generates a List of numbers.

From ping /?:

Usage: ping [-t] [-a] [-n count] [-l size] [-f] [-i TTL] [-v TOS]
            [-r count] [-s count] [[-j host-list] | [-k host-list]]
            [-w timeout] [-R] [-S srcaddr] [-4] [-6] target_name

Options:
    -t             Ping the specified host until stopped.
                   To see statistics and continue - type Control-Break;
                   To stop - type Control-C.
    -a             Resolve addresses to hostnames.
    -n count       Number of echo requests to send.
    -l size        Send buffer size.
    -f             Set Don't Fragment flag in packet (IPv4-only).
    -i TTL         Time To Live.
    -v TOS         Type Of Service (IPv4-only. This setting has been deprecated
                   and has no effect on the type of service field in the IP Header).
    -r count       Record route for count hops (IPv4-only).
    -s count       Timestamp for count hops (IPv4-only).
    -j host-list   Loose source route along host-list (IPv4-only).
    -k host-list   Strict source route along host-list (IPv4-only).
    -w timeout     Timeout in milliseconds to wait for each reply.
    -R             Use routing header to test reverse route also (IPv6-only).
    -S srcaddr     Source address to use.
    -4             Force using IPv4.
    -6             Force using IPv6.

What's the use of "enum" in Java?

an Enum is a safe-type so you can't assign a new value at the runtime. Moreover you can use it in a switch statement (like an int).

Jmeter - Run .jmx file through command line and get the summary report in a excel

This would be the command line statement.

"%JMETER_HOME%\bin\jmeter.bat" -n -t <jmx test file path> -l <csv result file path> -Djmeter.save.saveservice.output_format=csv

How to calculate rolling / moving average using NumPy / SciPy?

If you just want a straightforward non-weighted moving average, you can easily implement it with np.cumsum, which may be is faster than FFT based methods:

EDIT Corrected an off-by-one wrong indexing spotted by Bean in the code. EDIT

def moving_average(a, n=3) :
    ret = np.cumsum(a, dtype=float)
    ret[n:] = ret[n:] - ret[:-n]
    return ret[n - 1:] / n

>>> a = np.arange(20)
>>> moving_average(a)
array([  1.,   2.,   3.,   4.,   5.,   6.,   7.,   8.,   9.,  10.,  11.,
        12.,  13.,  14.,  15.,  16.,  17.,  18.])
>>> moving_average(a, n=4)
array([  1.5,   2.5,   3.5,   4.5,   5.5,   6.5,   7.5,   8.5,   9.5,
        10.5,  11.5,  12.5,  13.5,  14.5,  15.5,  16.5,  17.5])

So I guess the answer is: it is really easy to implement, and maybe numpy is already a little bloated with specialized functionality.

How can I color dots in a xy scatterplot according to column value?

I answered a very similar question:

https://stackoverflow.com/a/15982217/1467082

You simply need to iterate over the series' .Points collection, and then you can assign the points' .Format.Fill.ForeColor.RGB value based on whatever criteria you need.

UPDATED

The code below will color the chart per the screenshot. This only assumes three colors are used. You can add additional case statements for other color values, and update the assignment of myColor to the appropriate RGB values for each.

screenshot

Option Explicit
Sub ColorScatterPoints()
    Dim cht As Chart
    Dim srs As Series
    Dim pt As Point
    Dim p As Long
    Dim Vals$, lTrim#, rTrim#
    Dim valRange As Range, cl As Range
    Dim myColor As Long

    Set cht = ActiveSheet.ChartObjects(1).Chart
    Set srs = cht.SeriesCollection(1)

   '## Get the series Y-Values range address:
    lTrim = InStrRev(srs.Formula, ",", InStrRev(srs.Formula, ",") - 1, vbBinaryCompare) + 1
    rTrim = InStrRev(srs.Formula, ",")
    Vals = Mid(srs.Formula, lTrim, rTrim - lTrim)
    Set valRange = Range(Vals)

    For p = 1 To srs.Points.Count
        Set pt = srs.Points(p)
        Set cl = valRange(p).Offset(0, 1) '## assume color is in the next column.

        With pt.Format.Fill
            .Visible = msoTrue
            '.Solid  'I commented this out, but you can un-comment and it should still work
            '## Assign Long color value based on the cell value
            '## Add additional cases as needed.
            Select Case LCase(cl)
                Case "red"
                    myColor = RGB(255, 0, 0)
                Case "orange"
                    myColor = RGB(255, 192, 0)
                Case "green"
                    myColor = RGB(0, 255, 0)
            End Select

            .ForeColor.RGB = myColor

        End With
    Next


End Sub

How to write to files using utl_file in oracle

Here is a robust function for using UTL_File.putline that includes the necessary error handling. It also handles headers, footers and a few other exceptional cases.

PROCEDURE usp_OUTPUT_ToFileAscii(p_Path IN VARCHAR2, p_FileName IN VARCHAR2, p_Input IN refCursor, p_Header in VARCHAR2, p_Footer IN VARCHAR2, p_WriteMode VARCHAR2) IS

              vLine VARCHAR2(30000);
              vFile UTL_FILE.file_type; 
              vExists boolean;
              vLength number;
              vBlockSize number;
    BEGIN

        UTL_FILE.fgetattr(p_path, p_FileName, vExists, vLength, vBlockSize);

                 FETCH p_Input INTO vLine;
         IF p_input%ROWCOUNT > 0
         THEN
            IF vExists THEN
               vFile := UTL_FILE.FOPEN_NCHAR(p_Path, p_FileName, p_WriteMode);
            ELSE
               --even if the append flag is passed if the file doesn't exist open it with W.
                vFile := UTL_FILE.FOPEN(p_Path, p_FileName, 'W');
            END IF;
            --GET HANDLE TO FILE
            IF p_Header IS NOT NULL THEN 
              UTL_FILE.PUT_LINE(vFile, p_Header);
            END IF;
            UTL_FILE.PUT_LINE(vFile, vLine);
            DBMS_OUTPUT.PUT_LINE('Record count > 0');

             --LOOP THROUGH CURSOR VAR
             LOOP
                FETCH p_Input INTO vLine;

                EXIT WHEN p_Input%NOTFOUND;

                UTL_FILE.PUT_LINE(vFile, vLine);

             END LOOP;


             IF p_Footer IS NOT NULL THEN 
                UTL_FILE.PUT_LINE(vFile, p_Footer);
             END IF;

             CLOSE p_Input;
             UTL_FILE.FCLOSE(vFile);
        ELSE
          DBMS_OUTPUT.PUT_LINE('Record count = 0');

        END IF; 


    EXCEPTION
       WHEN UTL_FILE.INVALID_PATH THEN 
           DBMS_OUTPUT.PUT_LINE ('invalid_path'); 
           DBMS_OUTPUT.PUT_LINE(SQLERRM);
           RAISE;

       WHEN UTL_FILE.INVALID_MODE THEN 
           DBMS_OUTPUT.PUT_LINE ('invalid_mode'); 
           DBMS_OUTPUT.PUT_LINE(SQLERRM);
           RAISE;

       WHEN UTL_FILE.INVALID_FILEHANDLE THEN 
           DBMS_OUTPUT.PUT_LINE ('invalid_filehandle'); 
           DBMS_OUTPUT.PUT_LINE(SQLERRM);
           RAISE;

       WHEN UTL_FILE.INVALID_OPERATION THEN 
           DBMS_OUTPUT.PUT_LINE ('invalid_operation'); 
           DBMS_OUTPUT.PUT_LINE(SQLERRM);
           RAISE;

       WHEN UTL_FILE.READ_ERROR THEN  
           DBMS_OUTPUT.PUT_LINE ('read_error');
           DBMS_OUTPUT.PUT_LINE(SQLERRM);
           RAISE;

       WHEN UTL_FILE.WRITE_ERROR THEN 
          DBMS_OUTPUT.PUT_LINE ('write_error'); 
          DBMS_OUTPUT.PUT_LINE(SQLERRM);
           RAISE;

       WHEN UTL_FILE.INTERNAL_ERROR THEN 
          DBMS_OUTPUT.PUT_LINE ('internal_error'); 
          DBMS_OUTPUT.PUT_LINE(SQLERRM);
          RAISE;            
       WHEN OTHERS THEN
          DBMS_OUTPUT.PUT_LINE ('other write error'); 
          DBMS_OUTPUT.PUT_LINE(SQLERRM);
          RAISE;
    END;

Removing a non empty directory programmatically in C or C++

C++17 has <experimental\filesystem> which is based on the boost version.

Use std::experimental::filesystem::remove_all to remove recursively.

If you need more control, try std::experimental::filesystem::recursive_directory_iterator.

You can also write your own recursion with the non-resursive version of the iterator.

namespace fs = std::experimental::filesystem;
void IterateRecursively(fs::path path)
{
  if (fs::is_directory(path))
  {
    for (auto & child : fs::directory_iterator(path))
      IterateRecursively(child.path());
  }

  std::cout << path << std::endl;
}

C# HttpWebRequest The underlying connection was closed: An unexpected error occurred on a send

For .Net 4 use:

ServicePointManager.SecurityProtocol = (SecurityProtocolType)768 | (SecurityProtocolType)3072;

Does Python have “private” variables in classes?

Python does not have any private variables like C++ or Java does. You could access any member variable at any time if wanted, too. However, you don't need private variables in Python, because in Python it is not bad to expose your classes member variables. If you have the need to encapsulate a member variable, you can do this by using "@property" later on without breaking existing client code.

In python the single underscore "_" is used to indicate, that a method or variable is not considered as part of the public api of a class and that this part of the api could change between different versions. You can use these methods/variables, but your code could break, if you use a newer version of this class.

The double underscore "__" does not mean a "private variable". You use it to define variables which are "class local" and which can not be easily overidden by subclasses. It mangles the variables name.

For example:

class A(object):
    def __init__(self):
        self.__foobar = None # will be automatically mangled to self._A__foobar

class B(A):
    def __init__(self):
        self.__foobar = 1 # will be automatically mangled to self._B__foobar

self.__foobar's name is automatically mangled to self._A__foobar in class A. In class B it is mangled to self._B__foobar. So every subclass can define its own variable __foobar without overriding its parents variable(s). But nothing prevents you from accessing variables beginning with double underscores. However, name-mangling prevents you from calling this variables /methods incidentally.

I strongly recommend to watch Raymond Hettingers talk "Pythons class development toolkit" from Pycon 2013 (should be available on Youtube), which gives a good example why and how you should use @property and "__"-instance variables.

If you have exposed public variables and you have the need to encapsulate them, then you can use @property. Therefore you can start with the simplest solution possible. You can leave member variables public unless you have a concrete reason to not do so. Here is an example:

class Distance:
    def __init__(self, meter):
        self.meter = meter


d = Distance(1.0)
print(d.meter)
# prints 1.0

class Distance:
    def __init__(self, meter):
        # Customer request: Distances must be stored in millimeters.
        # Public available internals must be changed.
        # This would break client code in C++.
        # This is why you never expose public variables in C++ or Java.
        # However, this is python.
        self.millimeter = meter * 1000

    # In python we have @property to the rescue.
    @property
    def meter(self):
        return self.millimeter *0.001

    @meter.setter
    def meter(self, value):
        self.millimeter = meter * 1000

d = Distance(1.0)
print(d.meter)
# prints 1.0

Text in Border CSS HTML

You can do something like this, where you set a negative margin on the h1 (or whatever header you are using)

div{
    height:100px;
    width:100px;
    border:2px solid black;
}

h1{
    width:30px;
    margin-top:-10px;
    margin-left:5px;
    background:white;
}

Note: you need to set a background as well as a width on the h1

Example: http://jsfiddle.net/ZgEMM/


EDIT

To make it work with hiding the div, you could use some jQuery like this

$('a').click(function(){
    var a = $('h1').detach();
    $('div').hide();
    $(a).prependTo('body');    
});

(You will need to modify...)

Example #2: http://jsfiddle.net/ZgEMM/4/

What does 'synchronized' mean?

In java to prevent multiple threads manipulating a shared variable we use synchronized keyword. Lets understand it with help of the following example:

In the example I have defined two threads and named them increment and decrement. Increment thread increases the value of shared variable (counter) by the same amount the decrement thread decreases it i.e 5000 times it is increased (which result in 5000 + 0 = 5000) and 5000 times we decrease (which result in 5000 - 5000 = 0).

Program without synchronized keyword:

class SynchronizationDemo {

    public static void main(String[] args){

        Buffer buffer = new Buffer();                   

        MyThread incThread = new MyThread(buffer, "increment");
        MyThread decThread = new MyThread(buffer, "decrement"); 

        incThread.start();
        decThread.start();  
       
        try {
          incThread.join();
          decThread.join();
        }catch(InterruptedException e){ }

        System.out.println("Final counter: "+buffer.getCounter());
    }
}

class Buffer {
    private int counter = 0; 
    public void inc() { counter++; }
    public void dec() { counter--; } 
    public int getCounter() { return counter; }
}

class MyThread extends Thread {

    private String name;
    private Buffer buffer;

    public MyThread (Buffer aBuffer, String aName) {            
        buffer = aBuffer; 
        name = aName; 
    }

    public void run(){
        for (int i = 0; i <= 5000; i++){
            if (name.equals("increment"))
                buffer.inc();
            else
                buffer.dec();                           
        }
    }
}

If we run the above program we expect value of buffer to be same since incrementing and decrementing the buffer by same amount would result in initial value we started with right ?. Lets see the output:

enter image description here

As you can see no matter how many times we run the program we get a different result reason being each thread manipulated the counter at the same time. If we could manage to let the one thread to first increment the shared variable and then second to decrement it or vice versa we will then get the right result that is exactly what can be done with synchronized keyword by just adding synchronized keyword before the inc and dec methods of Buffer like this:

Program with synchronized keyword:

// rest of the code

class Buffer {
    private int counter = 0; 
    // added synchronized keyword to let only one thread
    // be it inc or dec thread to manipulate data at a time
    public synchronized void inc() { counter++; }
    public synchronized void dec() { counter--; } 
    public int getCounter() { return counter; }
}

// rest of the code

and the output:

enter image description here

no matter how many times we run it we get the same output as 0

Return value of x = os.system(..)

os.system('command') returns a 16 bit number, which first 8 bits from left(lsb) talks about signal used by os to close the command, Next 8 bits talks about return code of command.

Refer my answer for more detail in What is the return value of os.system() in Python?

Bootstrap 4 Change Hamburger Toggler Color

Yes, just delete this span from your code: <span class="navbar-toggler-icon"></span> , then paste this font awesome icon that called bars: <i class="fas fa-bars"></i>, add a class to this icon, then put any color you want.

Then, the second step is to hide this icon from the devices that have width more than 992px (desktops width), due to this icon will appear in your interface at any device if you won't add this @media in your css code:

 /* Large devices (desktops, 992px and up) */
@media (min-width: 992px) { 
    /* the class you gave of the bars icon ? */
    .iconClass{
        display: none;
    }
    /* the bootstrap toogler button class */
    .navbar-toggler{
        display: none;
    }
}

It worked for me as well and I found it so easy.

How to use java.Set

It's difficult to answer this question with the information given. Nothing looks particularly wrong with how you are using HashSet.

Well, I'll hazard a guess that it's not a compilation issue and, when you say "getting errors," you mean "not getting the behavior [you] want."

I'll also go out on a limb and suggest that maybe your Block's equals an hashCode methods are not properly overridden.

Android - get children inside a View?

Here is a suggestion: you can get the ID (specified e.g. by android:id="@+id/..My Str..) which was generated by R by using its given name (e.g. My Str). A code snippet using getIdentifier() method would then be:

public int getIdAssignedByR(Context pContext, String pIdString)
{
    // Get the Context's Resources and Package Name
    Resources resources = pContext.getResources();
    String packageName  = pContext.getPackageName();

    // Determine the result and return it
    int result = resources.getIdentifier(pIdString, "id", packageName);
    return result;
}

From within an Activity, an example usage coupled with findViewById would be:

// Get the View (e.g. a TextView) which has the Layout ID of "UserInput"
int rID = getIdAssignedByR(this, "UserInput")
TextView userTextView = (TextView) findViewById(rID);

jQuery - checkbox enable/disable

<form name="frmChkForm" id="frmChkForm">
<input type="checkbox" name="chkcc9" id="chkAll">Check Me
<input type="checkbox" name="chk9[120]" class="chkGroup">
<input type="checkbox" name="chk9[140]" class="chkGroup">
<input type="checkbox" name="chk9[150]" class="chkGroup">
</form>

$("#chkAll").click(function() {
   $(".chkGroup").attr("checked", this.checked);
});

With added functionality to ensure the check all checkbox gets checked/dechecked if all individual checkboxes are checked:

$(".chkGroup").click(function() {
  $("#chkAll")[0].checked = $(".chkGroup:checked").length == $(".chkGroup").length;
});