Programs & Examples On #Spreadsheet

Use this tag for questions about spreadsheet apps, plug-ins, libraries, etc., where no more specific tag exists. A spreadsheet presents tabular data sets arranged in rows and columns, typically with tools for capturing, analyzing, and collaborating on that data. Each cell may contain alphanumeric text, numeric values, or formulas.

Selecting non-blank cells in Excel with VBA

This might be completely off base, but can't you just copy the whole column into a new spreadsheet and then sort the column? I'm assuming that you don't need to maintain the order integrity.

How can I quickly and easily convert spreadsheet data to JSON?

Assuming you really mean easiest and are not necessarily looking for a way to do this programmatically, you can do this:

  1. Add, if not already there, a row of "column Musicians" to the spreadsheet. That is, if you have data in columns such as:

    Rory Gallagher      Guitar
    Gerry McAvoy        Bass
    Rod de'Ath          Drums
    Lou Martin          Keyboards
    Donkey Kong Sioux   Self-Appointed Semi-official Stomper
    

    Note: you might want to add "Musician" and "Instrument" in row 0 (you might have to insert a row there)

  2. Save the file as a CSV file.

  3. Copy the contents of the CSV file to the clipboard

  4. Go to http://www.convertcsv.com/csv-to-json.htm

  5. Verify that the "First row is column names" checkbox is checked

  6. Paste the CSV data into the content area

  7. Mash the "Convert CSV to JSON" button

    With the data shown above, you will now have:

    [
      {
        "MUSICIAN":"Rory Gallagher",
        "INSTRUMENT":"Guitar"
      },
      {
        "MUSICIAN":"Gerry McAvoy",
        "INSTRUMENT":"Bass"
      },
      {
        "MUSICIAN":"Rod D'Ath",
        "INSTRUMENT":"Drums"
      },
      {
        "MUSICIAN":"Lou Martin",
        "INSTRUMENT":"Keyboards"
      }
      {
        "MUSICIAN":"Donkey Kong Sioux",
        "INSTRUMENT":"Self-Appointed Semi-Official Stomper"
      }
    ]
    

    With this simple/minimalistic data, it's probably not required, but with large sets of data, it can save you time and headache in the proverbial long run by checking this data for aberrations and abnormalcy.

  8. Go here: http://jsonlint.com/

  9. Paste the JSON into the content area

  10. Pres the "Validate" button.

If the JSON is good, you will see a "Valid JSON" remark in the Results section below; if not, it will tell you where the problem[s] lie so that you can fix it/them.

Importing Excel spreadsheet data into another Excel spreadsheet containing VBA

Data can be pulled into an excel from another excel through Workbook method or External reference or through Data Import facility.

If you want to read or even if you want to update another excel workbook, these methods can be used. We may not depend only on VBA for this.

For more info on these techniques, please click here to refer the article

Excel - find cell with same value in another worksheet and enter the value to the left of it

Assuming employee numbers are in the first column and their names are in the second:

=VLOOKUP(A1, Sheet2!A:B, 2,false)

EXCEL Multiple Ranges - need different answers for each range

Nested if's in Excel Are ugly:

=If(G2 < 1, .1, IF(G2 < 5,.15,if(G2 < 15,.2,if(G2 < 30,.5,if(G2 < 100,.1,1.3)))))

That should cover it.

How to convert a char array to a string?

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

using namespace std;

int main ()
{
  char *tmp = (char *)malloc(128);
  int n=sprintf(tmp, "Hello from Chile.");

  string tmp_str = tmp;


  cout << *tmp << " : is a char array beginning with " <<n <<" chars long\n" << endl;
  cout << tmp_str << " : is a string with " <<n <<" chars long\n" << endl;

 free(tmp); 
 return 0;
}

OUT:

H : is a char array beginning with 17 chars long

Hello from Chile. :is a string with 17 chars long

How do I import CSV file into a MySQL table?

I did it in simple way using phpmyadmin. I followed the steps by @Farhan but all data were eltered in single column. How I did:

  1. Created a CSV file and deleted the header row with column names. Kept only data.
  2. I created a table with column names matching the csv columns.
  3. Remember to assign appropriate types to each column.
  4. I just selected the import and went to import tab.
  5. In browse I selected the CSV file and kept all options as it is.
  6. To my surprise all the data got imported successfully in their appropriate columns.

How to execute shell command in Javascript

This depends entirely on the JavaScript environment. Please elaborate.

For example, in Windows Scripting, you do things like:

var shell = WScript.CreateObject("WScript.Shell");
shell.Run("command here");

Search a text file and print related lines in Python?

with open('file.txt', 'r') as searchfile:
    for line in searchfile:
        if 'searchphrase' in line:
            print line

With apologies to senderle who I blatantly copied.

@RequestParam vs @PathVariable

Both the annotations behave exactly in same manner.

Only 2 special characters '!' and '@' are accepted by the annotations @PathVariable and @RequestParam.

To check and confirm the behavior I have created a spring boot application that contains only 1 controller.

 @RestController 
public class Controller 
{
    @GetMapping("/pvar/{pdata}")
    public @ResponseBody String testPathVariable(@PathVariable(name="pdata") String pathdata)
    {
        return pathdata;
    }

    @GetMapping("/rpvar")
    public @ResponseBody String testRequestParam(@RequestParam("param") String paramdata)
    {
        return paramdata;
    }
}

Hitting following Requests I got the same response:

  1. localhost:7000/pvar/!@#$%^&*()_+-=[]{}|;':",./<>?
  2. localhost:7000/rpvar?param=!@#$%^&*()_+-=[]{}|;':",./<>?

!@ was received as response in both the requests

Iterating Over Dictionary Key Values Corresponding to List in Python

You have several options for iterating over a dictionary.

If you iterate over the dictionary itself (for team in league), you will be iterating over the keys of the dictionary. When looping with a for loop, the behavior will be the same whether you loop over the dict (league) itself, or league.keys():

for team in league.keys():
    runs_scored, runs_allowed = map(float, league[team])

You can also iterate over both the keys and the values at once by iterating over league.items():

for team, runs in league.items():
    runs_scored, runs_allowed = map(float, runs)

You can even perform your tuple unpacking while iterating:

for team, (runs_scored, runs_allowed) in league.items():
    runs_scored = float(runs_scored)
    runs_allowed = float(runs_allowed)

WCF named pipe minimal example

Try this.

Here is the service part.

[ServiceContract]
public interface IService
{
    [OperationContract]
    void  HelloWorld();
}

public class Service : IService
{
    public void HelloWorld()
    {
        //Hello World
    }
}

Here is the Proxy

public class ServiceProxy : ClientBase<IService>
{
    public ServiceProxy()
        : base(new ServiceEndpoint(ContractDescription.GetContract(typeof(IService)),
            new NetNamedPipeBinding(), new EndpointAddress("net.pipe://localhost/MyAppNameThatNobodyElseWillUse/helloservice")))
    {

    }
    public void InvokeHelloWorld()
    {
        Channel.HelloWorld();
    }
}

And here is the service hosting part.

var serviceHost = new ServiceHost
        (typeof(Service), new Uri[] { new Uri("net.pipe://localhost/MyAppNameThatNobodyElseWillUse") });
    serviceHost.AddServiceEndpoint(typeof(IService), new NetNamedPipeBinding(), "helloservice");
    serviceHost.Open();

    Console.WriteLine("Service started. Available in following endpoints");
    foreach (var serviceEndpoint in serviceHost.Description.Endpoints)
    {
        Console.WriteLine(serviceEndpoint.ListenUri.AbsoluteUri);
    }

JNI converting jstring to char *

Here's a a couple of useful link that I found when I started with JNI

http://en.wikipedia.org/wiki/Java_Native_Interface
http://download.oracle.com/javase/1.5.0/docs/guide/jni/spec/functions.html

concerning your problem you can use this

JNIEXPORT void JNICALL Java_ClassName_MethodName(JNIEnv *env, jobject obj, jstring javaString)   
{
   const char *nativeString = env->GetStringUTFChars(javaString, 0);

   // use your string

   env->ReleaseStringUTFChars(javaString, nativeString);
}

C-like structures in Python

Some the answers here are massively elaborate. The simplest option I've found is (from: http://norvig.com/python-iaq.html):

class Struct:
    "A structure that can have any fields defined."
    def __init__(self, **entries): self.__dict__.update(entries)

Initialising:

>>> options = Struct(answer=42, linelen=80, font='courier')
>>> options.answer
42

adding more:

>>> options.cat = "dog"
>>> options.cat
dog

edit: Sorry didn't see this example already further down.

Types in Objective-C on iOS

This is a good overview:

http://reference.jumpingmonkey.org/programming_languages/objective-c/types.html

or run this code:

32 bit process:

  NSLog(@"Primitive sizes:");
  NSLog(@"The size of a char is: %d.", sizeof(char));
  NSLog(@"The size of short is: %d.", sizeof(short));
  NSLog(@"The size of int is: %d.", sizeof(int));
  NSLog(@"The size of long is: %d.", sizeof(long));
  NSLog(@"The size of long long is: %d.", sizeof(long long));
  NSLog(@"The size of a unsigned char is: %d.", sizeof(unsigned char));
  NSLog(@"The size of unsigned short is: %d.", sizeof(unsigned short));
  NSLog(@"The size of unsigned int is: %d.", sizeof(unsigned int));
  NSLog(@"The size of unsigned long is: %d.", sizeof(unsigned long));
  NSLog(@"The size of unsigned long long is: %d.", sizeof(unsigned long long));
  NSLog(@"The size of a float is: %d.", sizeof(float));
  NSLog(@"The size of a double is %d.", sizeof(double));

  NSLog(@"Ranges:");
  NSLog(@"CHAR_MIN:   %c",   CHAR_MIN);
  NSLog(@"CHAR_MAX:   %c",   CHAR_MAX);
  NSLog(@"SHRT_MIN:   %hi",  SHRT_MIN);    // signed short int
  NSLog(@"SHRT_MAX:   %hi",  SHRT_MAX);
  NSLog(@"INT_MIN:    %i",   INT_MIN);
  NSLog(@"INT_MAX:    %i",   INT_MAX);
  NSLog(@"LONG_MIN:   %li",  LONG_MIN);    // signed long int
  NSLog(@"LONG_MAX:   %li",  LONG_MAX);
  NSLog(@"ULONG_MAX:  %lu",  ULONG_MAX);   // unsigned long int
  NSLog(@"LLONG_MIN:  %lli", LLONG_MIN);   // signed long long int
  NSLog(@"LLONG_MAX:  %lli", LLONG_MAX);
  NSLog(@"ULLONG_MAX: %llu", ULLONG_MAX);  // unsigned long long int

When run on an iPhone 3GS (iPod Touch and older iPhones should yield the same result) you get:

Primitive sizes:
The size of a char is: 1.                
The size of short is: 2.                 
The size of int is: 4.                   
The size of long is: 4.                  
The size of long long is: 8.             
The size of a unsigned char is: 1.       
The size of unsigned short is: 2.        
The size of unsigned int is: 4.          
The size of unsigned long is: 4.         
The size of unsigned long long is: 8.    
The size of a float is: 4.               
The size of a double is 8.               
Ranges:                                  
CHAR_MIN:   -128                         
CHAR_MAX:   127                          
SHRT_MIN:   -32768                       
SHRT_MAX:   32767                        
INT_MIN:    -2147483648                  
INT_MAX:    2147483647                   
LONG_MIN:   -2147483648                  
LONG_MAX:   2147483647                   
ULONG_MAX:  4294967295                   
LLONG_MIN:  -9223372036854775808         
LLONG_MAX:  9223372036854775807          
ULLONG_MAX: 18446744073709551615 

64 bit process:

The size of a char is: 1.
The size of short is: 2.
The size of int is: 4.
The size of long is: 8.
The size of long long is: 8.
The size of a unsigned char is: 1.
The size of unsigned short is: 2.
The size of unsigned int is: 4.
The size of unsigned long is: 8.
The size of unsigned long long is: 8.
The size of a float is: 4.
The size of a double is 8.
Ranges:
CHAR_MIN:   -128
CHAR_MAX:   127
SHRT_MIN:   -32768
SHRT_MAX:   32767
INT_MIN:    -2147483648
INT_MAX:    2147483647
LONG_MIN:   -9223372036854775808
LONG_MAX:   9223372036854775807
ULONG_MAX:  18446744073709551615
LLONG_MIN:  -9223372036854775808
LLONG_MAX:  9223372036854775807
ULLONG_MAX: 18446744073709551615

What does LINQ return when the results are empty

In Linq-to-SQL if you try to get the first element on a query with no results you will get sequence contains no elements error. I can assure you that the mentioned error is not equal to object reference not set to an instance of an object. in conclusion no, it won't return null since null can't say sequence contains no elements it will always say object reference not set to an instance of an object ;)

Firestore Getting documents id from collection

To obtain the id of the documents in a collection, you must use snapshotChanges()

    this.shirtCollection = afs.collection<Shirt>('shirts');
    // .snapshotChanges() returns a DocumentChangeAction[], which contains
    // a lot of information about "what happened" with each change. If you want to
    // get the data and the id use the map operator.
    this.shirts = this.shirtCollection.snapshotChanges().map(actions => {
      return actions.map(a => {
        const data = a.payload.doc.data() as Shirt;
        const id = a.payload.doc.id;
        return { id, ...data };
      });
    });

Documentation https://github.com/angular/angularfire2/blob/7eb3e51022c7381dfc94ffb9e12555065f060639/docs/firestore/collections.md#example

How to convert an Stream into a byte[] in C#?

Stream s;
int len = (int)s.Length;
byte[] b = new byte[len];
int pos = 0;
while((r = s.Read(b, pos, len - pos)) > 0) {
    pos += r;
}

A slightly more complicated solution is necesary is s.Length exceeds Int32.MaxValue. But if you need to read a stream that large into memory, you might want to think about a different approach to your problem.

Edit: If your stream does not support the Length property, modify using Earwicker's workaround.

public static class StreamExtensions {
    // Credit to Earwicker
    public static void CopyStream(this Stream input, Stream output) {
        byte[] b = new byte[32768];
        int r;
        while ((r = input.Read(b, 0, b.Length)) > 0) {
            output.Write(b, 0, r);
        }
    }
}

[...]

Stream s;
MemoryStream ms = new MemoryStream();
s.CopyStream(ms);
byte[] b = ms.GetBuffer();

How to get label of select option with jQuery?

Hi first give an id to the select as

<select id=theid>
<option value="test">label </option>
</select>

then you can call the selected label like that:

jQuery('#theid option:selected').text()

Can typescript export a function?

In my case I'm doing it like this:

 module SayHi {
    export default () => { console.log("Hi"); }
 }
 new SayHi();

How to compare 2 dataTables

or this, I did not implement the array comparison so you will also have some fun :)

public bool CompareTables(DataTable a, DataTable b)
{
    if(a.Rows.Count != b.Rows.Count)
    {
        // different size means different tables
        return false;
    }

    for(int rowIndex=0; rowIndex<a.Rows.Count; ++rowIndex)
    {
        if(!arraysHaveSameContent(a.Rows[rowIndex].ItemArray, b.Rows[rowIndex].ItemArray,))
        {
            return false;
        }
    }

    // Tables have same data
    return true;
}

private bool arraysHaveSameContent(object[] a, object[] b)
{
    // Here your super cool method to compare the two arrays with LINQ,
    // or if you are a loser do it with a for loop :D
}

How to check if type is Boolean

Sometimes we need a single way to check it. typeof not working for date etc. So I made it easy by

Date.prototype.getType() { return "date"; }

Also for Number, String, Boolean etc. we often need to check the type in a single way...

What are access specifiers? Should I inherit with private, protected or public?

what are Access Specifiers?

There are 3 access specifiers for a class/struct/Union in C++. These access specifiers define how the members of the class can be accessed. Of course, any member of a class is accessible within that class(Inside any member function of that same class). Moving ahead to type of access specifiers, they are:

Public - The members declared as Public are accessible from outside the Class through an object of the class.

Protected - The members declared as Protected are accessible from outside the class BUT only in a class derived from it.

Private - These members are only accessible from within the class. No outside Access is allowed.

An Source Code Example:

class MyClass
{
    public:
        int a;
    protected:
        int b;
    private:
        int c;
};

int main()
{
    MyClass obj;
    obj.a = 10;     //Allowed
    obj.b = 20;     //Not Allowed, gives compiler error
    obj.c = 30;     //Not Allowed, gives compiler error
}

Inheritance and Access Specifiers

Inheritance in C++ can be one of the following types:

  • Private Inheritance
  • Public Inheritance
  • Protected inheritance

Here are the member access rules with respect to each of these:

First and most important rule Private members of a class are never accessible from anywhere except the members of the same class.

Public Inheritance:

All Public members of the Base Class become Public Members of the derived class &
All Protected members of the Base Class become Protected Members of the Derived Class.

i.e. No change in the Access of the members. The access rules we discussed before are further then applied to these members.

Code Example:

Class Base
{
    public:
        int a;
    protected:
        int b;
    private:
        int c;
};

class Derived:public Base
{
    void doSomething()
    {
        a = 10;  //Allowed 
        b = 20;  //Allowed
        c = 30;  //Not Allowed, Compiler Error
    }
};

int main()
{
    Derived obj;
    obj.a = 10;  //Allowed
    obj.b = 20;  //Not Allowed, Compiler Error
    obj.c = 30;  //Not Allowed, Compiler Error

}

Private Inheritance:

All Public members of the Base Class become Private Members of the Derived class &
All Protected members of the Base Class become Private Members of the Derived Class.

An code Example:

Class Base
{
    public:
      int a;
    protected:
      int b;
    private:
      int c;
};

class Derived:private Base   //Not mentioning private is OK because for classes it  defaults to private 
{
    void doSomething()
    {
        a = 10;  //Allowed 
        b = 20;  //Allowed
        c = 30;  //Not Allowed, Compiler Error
    }
};

class Derived2:public Derived
{
    void doSomethingMore()
    {
        a = 10;  //Not Allowed, Compiler Error, a is private member of Derived now
        b = 20;  //Not Allowed, Compiler Error, b is private member of Derived now
        c = 30;  //Not Allowed, Compiler Error
    }
};

int main()
{
    Derived obj;
    obj.a = 10;  //Not Allowed, Compiler Error
    obj.b = 20;  //Not Allowed, Compiler Error
    obj.c = 30;  //Not Allowed, Compiler Error

}

Protected Inheritance:

All Public members of the Base Class become Protected Members of the derived class &
All Protected members of the Base Class become Protected Members of the Derived Class.

A Code Example:

Class Base
{
    public:
        int a;
    protected:
        int b;
    private:
        int c;
};

class Derived:protected Base  
{
    void doSomething()
    {
        a = 10;  //Allowed 
        b = 20;  //Allowed
        c = 30;  //Not Allowed, Compiler Error
    }
};

class Derived2:public Derived
{
    void doSomethingMore()
    {
        a = 10;  //Allowed, a is protected member inside Derived & Derived2 is public derivation from Derived, a is now protected member of Derived2
        b = 20;  //Allowed, b is protected member inside Derived & Derived2 is public derivation from Derived, b is now protected member of Derived2
        c = 30;  //Not Allowed, Compiler Error
    }
};

int main()
{
    Derived obj;
    obj.a = 10;  //Not Allowed, Compiler Error
    obj.b = 20;  //Not Allowed, Compiler Error
    obj.c = 30;  //Not Allowed, Compiler Error
}

Remember the same access rules apply to the classes and members down the inheritance hierarchy.


Important points to note:

- Access Specification is per-Class not per-Object

Note that the access specification C++ work on per-Class basis and not per-object basis.
A good example of this is that in a copy constructor or Copy Assignment operator function, all the members of the object being passed can be accessed.

- A Derived class can only access members of its own Base class

Consider the following code example:

class Myclass
{ 
    protected: 
       int x; 
}; 

class derived : public Myclass
{
    public: 
        void f( Myclass& obj ) 
        { 
            obj.x = 5; 
        } 
};

int main()
{
    return 0;
}

It gives an compilation error:

prog.cpp:4: error: ‘int Myclass::x’ is protected

Because the derived class can only access members of its own Base Class. Note that the object obj being passed here is no way related to the derived class function in which it is being accessed, it is an altogether different object and hence derived member function cannot access its members.


What is a friend? How does friend affect access specification rules?

You can declare a function or class as friend of another class. When you do so the access specification rules do not apply to the friended class/function. The class or function can access all the members of that particular class.

So do friends break Encapsulation?

No they don't, On the contrary they enhance Encapsulation!

friendship is used to indicate a intentional strong coupling between two entities.
If there exists a special relationship between two entities such that one needs access to others private or protected members but You do not want everyone to have access by using the public access specifier then you should use friendship.

Copying files from one directory to another in Java

    File file = fileChooser.getSelectedFile();
    String selected = fc.getSelectedFile().getAbsolutePath();
     File srcDir = new File(selected);
     FileInputStream fii;
     FileOutputStream fio;
    try {
         fii = new FileInputStream(srcDir);
         fio = new FileOutputStream("C:\\LOvE.txt");
         byte [] b=new byte[1024];
         int i=0;
        try {
            while ((fii.read(b)) > 0)
            {

              System.out.println(b);
              fio.write(b);
            }
            fii.close();
            fio.close();

Executing a batch file in a remote machine through PsExec

Here's my current solution to run any code remotely on a given machine or list of machines asynchronously with logging, too!

@echo off
:: by Ralph Buchfelder, thanks to Mark Russinovich and Rob van der Woude for their work!
:: requires PsExec.exe to be in the same directory (download from http://technet.microsoft.com/de-de/sysinternals/bb897553.aspx)
:: troubleshoot remote commands with PsExec arguments -i or -s if neccessary (see http://forum.sysinternals.com/pstools_forum8.html)
:: will run *in parallel* on a list of remote pcs (if given); to run serially please remove 'START "" CMD.EXE /C' from the psexec call


:: help
if '%1' =='-h' (
 echo.
 echo %~n0
 echo.
 echo Runs a command on one or many remote machines. If no input parameters
 echo are given you will be asked for a target remote machine.
 echo.
 echo You will be prompted for remote credentials with elevated privileges.
 echo.
 echo UNC paths and local paths can be supplied.
 echo Commands will be executed on the remote side just the way you typed
 echo them, so be sure to mind extensions and the path variable!
 echo.
 echo Please note that PsExec.exe must be allowed on remote machines, i.e.
 echo not blocked by firewall or antivirus solutions.
 echo.
 echo Syntax: %~n0 [^<inputfile^>]
 echo.
 echo     inputfile      = a plain text file ^(one hostname or ip address per line^)
 echo.
 echo.
 echo Example:
 echo %~n0 mylist.txt
 exit /b 0
)


:checkAdmin
>nul 2>&1 "%SYSTEMROOT%\system32\cacls.exe" "%SYSTEMROOT%\system32\config\system"
if '%errorlevel%' neq '0' (
 echo Set UAC = CreateObject^("Shell.Application"^) > "%temp%\getadmin.vbs"
 echo UAC.ShellExecute "%~s0", "", "", "runas", 1 >> "%temp%\getadmin.vbs"
 "%temp%\getadmin.vbs"
 del "%temp%\getadmin.vbs"
 exit /B
)
set ADMINTESTDIR=%WINDIR%\System32\Test_%RANDOM%
mkdir "%ADMINTESTDIR%" 2>NUL
if errorlevel 1 (
 cls
 echo ERROR: This script requires elevated privileges!
 echo.
 echo Launch by Right-Click / Run as Administrator ...
 pause
 exit /b 1
) else (
 rd /s /q "%ADMINTESTDIR%"
 echo Running with elevated privileges...
)
echo.


:checkRequirements
if not exist "%~dp0PsExec.exe" (
 echo PsExec.exe from Sysinternals/Microsoft not found 
 echo in %~dp0
 echo.
 echo Download from http://technet.microsoft.com/de-de/sysinternals/bb897553.aspx
 echo.
 pause
 exit /B
)


:environment
setlocal
echo.
echo %~n0
echo _____________________________
echo.
echo Working directory:  %cd%\
echo Script directory:   %~dp0
echo.
SET /P REMOTE_USER=Domain\Administrator : 
SET "psCommand=powershell -Command "$pword = read-host 'Kennwort' -AsSecureString ; ^
    $BSTR=[System.Runtime.InteropServices.Marshal]::SecureStringToBSTR($pword); ^
        [System.Runtime.InteropServices.Marshal]::PtrToStringAuto($BSTR)""
for /f "usebackq delims=" %%p in (`%psCommand%`) do set REMOTE_PASS=%%p
if NOT DEFINED REMOTE_PASS SET /P REMOTE_PASS=Password             : 
echo.
if '%1' =='' goto menu
SET REMOTE_LIST=%1


:inputMultipleTargets
if not exist %REMOTE_LIST% (
 echo File %REMOTE_LIST% not found
 goto menu
)
type %REMOTE_LIST% >nul
if '%errorlevel%' neq '0' (
 echo Access denied %REMOTE_LIST%
 goto menu
)
set batchProcessing=true
echo Batch processing:   %REMOTE_LIST%   ...
ping -n 2 127.0.0.1 >nul
goto runOnce


:menu
if exist "%~dp0last.computer"  set /p LAST_COMPUTER=<"%~dp0last.computer"
if exist "%~dp0last.listing"   set /p LAST_LISTING=<"%~dp0last.listing"
if exist "%~dp0last.directory" set /p LAST_DIRECTORY=<"%~dp0last.directory"
if exist "%~dp0last.command"   set /p LAST_COMMAND=<"%~dp0last.command"
if exist "%~dp0last.timestamp" set /p LAST_TIMESTAMP=<"%~dp0last.timestamp"
echo.
echo.
echo                (1)  select target computer [default]
echo                (2)  select multiple computers
echo                     -----------------------------------
echo                     last target : %LAST_COMPUTER%
echo                     last listing: %LAST_LISTING%
echo                     last path   : %LAST_DIRECTORY%
echo                     last command: %LAST_COMMAND%
echo                     last run    : %LAST_TIMESTAMP%
echo                     -----------------------------------
echo                (0)  exit
echo.
echo ENTER your choice.
echo.
echo.
:mychoice
SET /P mychoice=(0, 1, ...): 
if NOT DEFINED mychoice  goto promptSingleTarget
if "%mychoice%"=="1"     goto promptSingleTarget
if "%mychoice%"=="2"     goto promptMultipleTargets
if "%mychoice%"=="0"     goto end
goto mychoice


:promptMultipleTargets
echo.
echo Please provide an input file
echo [one IP address or hostname per line]
SET /P REMOTE_LIST=Filename             : 
goto inputMultipleTargets


:promptSingleTarget
SET batchProcessing=
echo.
echo Please provide a hostname
SET /P REMOTE_COMPUTER=Target computer      : 
goto runOnce


:runOnce
cls
echo Note: Paths are mandatory for CMD-commands (e.g. dir,copy) to work!
echo       Paths are provided on the remote machine via PUSHD.
echo.
SET /P REMOTE_PATH=UNC-Path or folder : 
SET /P REMOTE_CMD=Command with params: 
SET REMOTE_TIMESTAMP=%DATE% %TIME:~0,8%
echo.
echo Remote command starting (%REMOTE_PATH%\%REMOTE_CMD%) on %REMOTE_TIMESTAMP%...
if not defined batchProcessing goto runOnceSingle


:runOnceMulti
REM do for each line; this circumvents PsExec's @file to have stdouts separately
SET REMOTE_LOG=%~dp0\log\%REMOTE_LIST%
if not exist %REMOTE_LOG% md %REMOTE_LOG%
for /F "tokens=*" %%A in (%REMOTE_LIST%) do (
 if "%REMOTE_PATH%" =="" START "" CMD.EXE /C ^(%~dp0PSEXEC -u %REMOTE_USER% -p %REMOTE_PASS% -h -accepteula \\%%A cmd /c "%REMOTE_CMD%" ^>"%REMOTE_LOG%\%%A.log" 2^>"%REMOTE_LOG%\%%A_debug.log" ^)
 if not "%REMOTE_PATH%" =="" START "" CMD.EXE /C ^(%~dp0PSEXEC -u %REMOTE_USER% -p %REMOTE_PASS% -h -accepteula \\%%A cmd /c "pushd %REMOTE_PATH% && %REMOTE_CMD% & popd" ^>"%REMOTE_LOG%\%%A.log" 2^>"%REMOTE_LOG%\%%A_debug.log" ^)
)
goto restart


:runOnceSingle
SET REMOTE_LOG=%~dp0\log
if not exist %REMOTE_LOG% md %REMOTE_LOG%
if "%REMOTE_PATH%" =="" %~dp0PSEXEC -u %REMOTE_USER% -p %REMOTE_PASS% -h -accepteula \\%REMOTE_COMPUTER% cmd /c "%REMOTE_CMD%" >"%REMOTE_LOG%\%REMOTE_COMPUTER%.log" 2>"%REMOTE_LOG%\%REMOTE_COMPUTER%_debug.log"
if not "%REMOTE_PATH%" =="" %~dp0PSEXEC -u %REMOTE_USER% -p %REMOTE_PASS% -h -accepteula \\%REMOTE_COMPUTER% cmd /c "pushd %REMOTE_PATH% && %REMOTE_CMD% & popd" >"%REMOTE_LOG%\%REMOTE_COMPUTER%.log" 2>"%REMOTE_LOG%\%REMOTE_COMPUTER%_debug.log"
goto restart


:restart
echo.
echo.
echo Batch completed. Finished with last errorlevel %errorlevel% .
echo All outputs have been saved to %~dp0log\%REMOTE_TIMESTAMP%\.
echo %REMOTE_PATH% >"%~dp0last.directory"
echo %REMOTE_CMD% >"%~dp0last.command"
echo %REMOTE_LIST% >"%~dp0last.listing"
echo %REMOTE_COMPUTER% >"%~dp0last.computer"
echo %REMOTE_TIMESTAMP% >"%~dp0last.timestamp"
SET REMOTE_PATH=
SET REMOTE_CMD=
SET REMOTE_LIST=
SET REMOTE_COMPUTER=
SET REMOTE_LOG=
SET REMOTE_TIMESTAMP=
ping -n 2 127.0.0.1 >nul
goto menu


:end
SET REMOTE_USER=
SET REMOTE_PASS=

How best to determine if an argument is not sent to the JavaScript function

If you are using jQuery, one option that is nice (especially for complicated situations) is to use jQuery's extend method.

function foo(options) {

    default_options = {
        timeout : 1000,
        callback : function(){},
        some_number : 50,
        some_text : "hello world"
    };

    options = $.extend({}, default_options, options);
}

If you call the function then like this:

foo({timeout : 500});

The options variable would then be:

{
    timeout : 500,
    callback : function(){},
    some_number : 50,
    some_text : "hello world"
};

How do I insert a JPEG image into a python Tkinter window?

Try this:

import tkinter as tk
from PIL import ImageTk, Image

#This creates the main window of an application
window = tk.Tk()
window.title("Join")
window.geometry("300x300")
window.configure(background='grey')

path = "Aaron.jpg"

#Creates a Tkinter-compatible photo image, which can be used everywhere Tkinter expects an image object.
img = ImageTk.PhotoImage(Image.open(path))

#The Label widget is a standard Tkinter widget used to display a text or image on the screen.
panel = tk.Label(window, image = img)

#The Pack geometry manager packs widgets in rows or columns.
panel.pack(side = "bottom", fill = "both", expand = "yes")

#Start the GUI
window.mainloop()

Related docs: ImageTk Module, Tkinter Label Widget, Tkinter Pack Geometry Manager

How to create a timer using tkinter?

The root.after(ms, func) is the method you need to use. Just call it once before the mainloop starts and reschedule it inside the bound function every time it is called. Here is an example:

from tkinter import *
import time


def update_clock():
    timer_label.config(text=time.strftime('%H:%M:%S',time.localtime()),
                  font='Times 25')  # change the text of the time_label according to the current time
    root.after(100, update_clock)  # reschedule update_clock function to update time_label every 100 ms

root = Tk()  # create the root window
timer_label = Label(root, justify='center')  # create the label for timer
timer_label.pack()  # show the timer_label using pack geometry manager
root.after(0, update_clock)  # schedule update_clock function first call
root.mainloop()  # start the root window mainloop

React router nav bar example

Yes, Daniel is correct, but to expand upon his answer, your primary app component would need to have a navbar component within it. That way, when you render the primary app (any page under the '/' path), it would also display the navbar. I am guessing that you wouldn't want your login page to display the navbar, so that shouldn't be a nested component, and should instead be by itself. So your routes would end up looking something like this:

<Router>
  <Route path="/" component={App}>
    <Route path="page1" component={Page1} />
    <Route path="page2" component={Page2} />
  </Route>
  <Route path="/login" component={Login} />
</Router>

And the other components would look something like this:

var NavBar = React.createClass({
  render() {
    return (
      <div>
        <ul>
          <a onClick={() => history.push('page1') }>Page 1</a>
          <a onClick={() => history.push('page2') }>Page 2</a>
        </ul>
      </div>
    )
  }
});

var App = React.createClass({
  render() {
    return (
      <div>
        <NavBar />
        <div>Other Content</div>
        {this.props.children}
      </div>
    )
  }
});

What is the difference between ELF files and bin files?

A bin file is just the bits and bytes that go into the rom or a particular address from which you will run the program. You can take this data and load it directly as is, you need to know what the base address is though as that is normally not in there.

An elf file contains the bin information but it is surrounded by lots of other information, possible debug info, symbols, can distinguish code from data within the binary. Allows for more than one chunk of binary data (when you dump one of these to a bin you get one big bin file with fill data to pad it to the next block). Tells you how much binary you have and how much bss data is there that wants to be initialised to zeros (gnu tools have problems creating bin files correctly).

The elf file format is a standard, arm publishes its enhancements/variations on the standard. I recommend everyone writes an elf parsing program to understand what is in there, dont bother with a library, it is quite simple to just use the information and structures in the spec. Helps to overcome gnu problems in general creating .bin files as well as debugging linker scripts and other things that can help to mess up your bin or elf output.

round() for float in C++

It's usually implemented as floor(value + 0.5).

Edit: and it's probably not called round since there are at least three rounding algorithms I know of: round to zero, round to closest integer, and banker's rounding. You are asking for round to closest integer.

ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)

By experience I say that you need to check if the server is running first and then try configuring MySQL. The last solution is to re-install MySQL.

Why would you use String.Equals over ==?

It's entirely likely that a large portion of the developer base comes from a Java background where using == to compare strings is wrong and doesn't work.

In C# there's no (practical) difference (for strings) as long as they are typed as string.

If they are typed as object or T then see other answers here that talk about generic methods or operator overloading as there you definitely want to use the Equals method.

PHP: Read Specific Line From File

$myFile = "4-21-11.txt";
$fh = fopen($myFile, 'r');
while(!feof($fh))
{
    $data[] = fgets($fh);  
    //Do whatever you want with the data in here
    //This feeds the file into an array line by line
}
fclose($fh);

How to extract HTTP response body from a Python requests call?

Your code is correct. I tested:

r = requests.get("http://www.google.com")
print(r.content)

And it returned plenty of content. Check the url, try "http://www.google.com". Cheers!

Regular expression for address field validation

I have succesfully used ;

Dim regexString = New stringbuilder
    With regexString
       .Append("(?<h>^[\d]+[ ])(?<s>.+$)|")                'find the 2013 1st ambonstreet 
       .Append("(?<s>^.*?)(?<h>[ ][\d]+[ ])(?<e>[\D]+$)|") 'find the 1-7-4 Dual Ampstreet 130 A
       .Append("(?<s>^[\D]+[ ])(?<h>[\d]+)(?<e>.*?$)|")    'find the Terheydenlaan 320 B3 
       .Append("(?<s>^.*?)(?<h>\d*?$)")                    'find the 245e oosterkade 9
    End With

    Dim Address As Match = Regex.Match(DataRow("customerAddressLine1"), regexString.ToString(), RegexOptions.Multiline)

    If Not String.IsNullOrEmpty(Address.Groups("s").Value) Then StreetName = Address.Groups("s").Value
    If Not String.IsNullOrEmpty(Address.Groups("h").Value) Then HouseNumber = Address.Groups("h").Value
    If Not String.IsNullOrEmpty(Address.Groups("e").Value) Then Extension = Address.Groups("e").Value

The regex will attempt to find a result, if there is none, it move to the next alternative. If no result is found, none of the 4 formats where present.

What is the default Precision and Scale for a Number in Oracle?

I believe the default precision is 38, default scale is zero. However the actual size of an instance of this column, is dynamic. It will take as much space as needed to store the value, or max 21 bytes.

Reset CSS display property to default value

If you have access to JavaScript, you can create an element and read its computed style.

function defaultValueOfCssPropertyForElement(cssPropertyName, elementTagName, opt_pseudoElement) {
    var pseudoElement = opt_pseudoElement || null;
    var element = document.createElement(elementTagName);
    document.body.appendChild(element);
    var computedStyle = getComputedStyle(element, pseudoElement)[cssPropertyName];
    element.remove();
    return computedStyle;
}

// Usage:
defaultValueOfCssPropertyForElement('display', 'div'); // Output: 'block'
defaultValueOfCssPropertyForElement('content', 'div', ':after'); // Output: 'none'

Jquery checking success of ajax post

I was wondering, why they didnt provide in jquery itself, so i made a few changes in jquery file ,,, here are the changed code block:

original Code block:

    post: function( url, data, callback, type ) {
    // shift arguments if data argument was omited
    if ( jQuery.isFunction( data ) ) {
        type = type || callback;
        callback = data;
        data = {};
    }

    return jQuery.ajax({
        type: "POST",
        url: url,
        data: data,
        success: callback,
        dataType: type
    });  

Changed Code block:

        post: function (url, data, callback, failcallback, type) {
        if (type === undefined || type === null) {
            if (!jQuery.isFunction(failcallback)) { 
            type=failcallback
        }
        else if (!jQuery.isFunction(callback)) {
            type = callback
        }
        }
        if (jQuery.isFunction(data) && jQuery.isFunction(callback)) {
            failcallback = callback;

        }
        // shift arguments if data argument was omited
        if (jQuery.isFunction(data)) {
            type = type || callback;
            callback = data;
            data = {};

        }


        return jQuery.ajax({
            type: "POST",
            url: url,
            data: data,
            success: callback,
            error:failcallback,
            dataType: type
        });
    },

This should help the one trying to catch error on $.Post in jquery.

Updated: Or there is another way to do this is :

   $.post(url,{},function(res){
        //To do write if call is successful
   }).error(function(p1,p2,p3){
             //To do Write if call is failed
          });

The server is not responding (or the local MySQL server's socket is not correctly configured) in wamp server

I use XAMPP and had the same error. I used Paul Gobée solution above and it worked for me. I navigated to C:\xampp\mysql\bin\mysqld-debug.exe and upon starting the .exe my Windows Firewall popped up asking for permission. Once I allowed it, it worked fine. I would have commented under his post but I do not have that much rep yet... sry! Just wanted to let everyone know this worked for me as well.

Find CRLF in Notepad++

Maybe you can use TextFX plugins

In TextFX, go to textfx edit ? delete blank lines

iOS 11, 12, and 13 installed certificates not trusted automatically (self signed)

This has happened to me also, after undating to IOS11 on my iPhone. When I try to connect to the corporate network it bring up the corporate cert and says it isn't trusted. I press the 'trust' button and the connection fails and the cert does not appear in the trusted certs list.

Can an Option in a Select tag carry multiple values?

In HTML

<SELECT NAME="Testing" id="Testing">  
  <OPTION VALUE="1,2010"> One  
  <OPTION VALUE="2,2122"> Two  
  <OPTION VALUE="3,0"> Three
</SELECT>

For JS

  var valueOne= $('#Testing').val().split(',')[0];
  var valueTwo =$('#Testing').val().split(',')[1];
  console.log(valueOne); //output 1
  console.log(valueTwo); //output 2010

OR FOR PHP

  $selectedValue= explode(',', $value);
  $valueOne= $exploded_value[0]; //output 1
  $valueTwo= $exploded_value[1]; //output 2010

what's data-reactid attribute in html?

Custom Data attribute in HTML5

Would like to quote Ian's comment in my answer:

It's just an attribute (a valid one) on the element that you can use to store data/info about it.

This code then retrieves it later in the event handler, and uses it to find the target output element. It effectively stores the class of the div where its text should be outputted.

reactid is just a suffix, you can have any name here eg: data-Ayman.

If you want to find the difference check the fiddles in this SO answer and comment.

Min/Max-value validators in asp.net mvc

A complete example of how this could be done. To avoid having to write client-side validation scripts, the existing ValidationType = "range" has been used.

public class MinValueAttribute : ValidationAttribute, IClientValidatable
{
    private readonly double _minValue;

    public MinValueAttribute(double minValue)
    {
        _minValue = minValue;
        ErrorMessage = "Enter a value greater than or equal to " + _minValue;  
    }

    public MinValueAttribute(int minValue)
    {
        _minValue = minValue;
        ErrorMessage = "Enter a value greater than or equal to " + _minValue;
    }

    public override bool IsValid(object value)
    {
        return Convert.ToDouble(value) >= _minValue;
    }

    public IEnumerable<ModelClientValidationRule> GetClientValidationRules(ModelMetadata metadata, ControllerContext context)
    {
        var rule = new ModelClientValidationRule();
        rule.ErrorMessage = ErrorMessage;
        rule.ValidationParameters.Add("min", _minValue);
        rule.ValidationParameters.Add("max", Double.MaxValue);
        rule.ValidationType = "range";
        yield return rule;
    }

}

Windows equivalent of the 'tail' command

You could get CoreUtils from GnuWin32, which is a collection of standard unix tools, ported to Windows.

It, among other things, contains head.

JQuery: dynamic height() with window resize()

I feel like there should be a no javascript solution, but how is this?

http://jsfiddle.net/NfmX3/2/

$(window).resize(function() {
    $('#content').height($(window).height() - 46);
});

$(window).trigger('resize');

Count unique values with pandas per groups

You need nunique:

df = df.groupby('domain')['ID'].nunique()

print (df)
domain
'facebook.com'    1
'google.com'      1
'twitter.com'     2
'vk.com'          3
Name: ID, dtype: int64

If you need to strip ' characters:

df = df.ID.groupby([df.domain.str.strip("'")]).nunique()
print (df)
domain
facebook.com    1
google.com      1
twitter.com     2
vk.com          3
Name: ID, dtype: int64

Or as Jon Clements commented:

df.groupby(df.domain.str.strip("'"))['ID'].nunique()

You can retain the column name like this:

df = df.groupby(by='domain', as_index=False).agg({'ID': pd.Series.nunique})
print(df)
    domain  ID
0       fb   1
1      ggl   1
2  twitter   2
3       vk   3

The difference is that nunique() returns a Series and agg() returns a DataFrame.

Quickest way to convert a base 10 number to any base in .NET?

I had a similar need, except I needed to do math on the "numbers" as well. I took some of the suggestions here and created a class that will do all this fun stuff. It allows for any unicode character to be used to represent a number and it works with decimals too.

This class is pretty easy to use. Just create a number as a type of New BaseNumber, set a few properties, and your off. The routines take care of switching between base 10 and base x automatically and the value you set is preserved in the base you set it in, so no accuracy is lost (until conversion that is, but even then precision loss should be very minimal since this routine uses Double and Long where ever possible).

I can't command on the speed of this routine. It is probably quite slow, so I'm not sure if it will suit the needs of the one who asked the question, but it certain is flexible, so hopefully someone else can use this.

For anyone else that may need this code for calculating the next column in Excel, I will include the looping code I used that leverages this class.

Public Class BaseNumber

    Private _CharacterArray As List(Of Char)

    Private _BaseXNumber As String
    Private _Base10Number As Double?

    Private NumberBaseLow As Integer
    Private NumberBaseHigh As Integer

    Private DecimalSeparator As Char = System.Globalization.CultureInfo.CurrentCulture.NumberFormat.NumberDecimalSeparator
    Private GroupSeparator As Char = System.Globalization.CultureInfo.CurrentCulture.NumberFormat.NumberGroupSeparator

    Public Sub UseCapsLetters()
        'http://unicodelookup.com
        TrySetBaseSet(65, 90)
    End Sub

    Public Function GetCharacterArray() As List(Of Char)
        Return _CharacterArray
    End Function

    Public Sub SetCharacterArray(CharacterArray As String)
        _CharacterArray = New List(Of Char)
        _CharacterArray.AddRange(CharacterArray.ToList)

        TrySetBaseSet(_CharacterArray)
    End Sub

    Public Sub SetCharacterArray(CharacterArray As List(Of Char))
        _CharacterArray = CharacterArray
        TrySetBaseSet(_CharacterArray)
    End Sub

    Public Sub SetNumber(Value As String)
        _BaseXNumber = Value
        _Base10Number = Nothing
    End Sub

    Public Sub SetNumber(Value As Double)
        _Base10Number = Value
        _BaseXNumber = Nothing
    End Sub

    Public Function GetBaseXNumber() As String
        If _BaseXNumber IsNot Nothing Then
            Return _BaseXNumber
        Else
            Return ToBaseString()
        End If
    End Function

    Public Function GetBase10Number() As Double
        If _Base10Number IsNot Nothing Then
            Return _Base10Number
        Else
            Return ToBase10()
        End If
    End Function

    Private Sub TrySetBaseSet(Values As List(Of Char))
        For Each value As Char In _BaseXNumber
            If Not Values.Contains(value) Then
                Throw New ArgumentOutOfRangeException("The string has a value, " & value & ", not contained in the selected 'base' set.")
                _CharacterArray.Clear()
                DetermineNumberBase()
            End If
        Next

        _CharacterArray = Values

    End Sub

    Private Sub TrySetBaseSet(LowValue As Integer, HighValue As Integer)

        Dim HighLow As KeyValuePair(Of Integer, Integer) = GetHighLow()

        If HighLow.Key < LowValue OrElse HighLow.Value > HighValue Then
            Throw New ArgumentOutOfRangeException("The string has a value not contained in the selected 'base' set.")
            _CharacterArray.Clear()
            DetermineNumberBase()
        End If

        NumberBaseLow = LowValue
        NumberBaseHigh = HighValue

    End Sub

    Private Function GetHighLow(Optional Values As List(Of Char) = Nothing) As KeyValuePair(Of Integer, Integer)
        If Values Is Nothing Then
            Values = _BaseXNumber.ToList
        End If

        Dim lowestValue As Integer = Convert.ToInt32(Values(0))
        Dim highestValue As Integer = Convert.ToInt32(Values(0))

        Dim currentValue As Integer

        For Each value As Char In Values

            If value <> DecimalSeparator AndAlso value <> GroupSeparator Then
                currentValue = Convert.ToInt32(value)
                If currentValue > highestValue Then
                    highestValue = currentValue
                End If
                If currentValue < lowestValue Then
                    currentValue = lowestValue
                End If
            End If
        Next

        Return New KeyValuePair(Of Integer, Integer)(lowestValue, highestValue)

    End Function

    Public Sub New(BaseXNumber As String)
        _BaseXNumber = BaseXNumber
        DetermineNumberBase()
    End Sub

    Public Sub New(BaseXNumber As String, NumberBase As Integer)
        Me.New(BaseXNumber, Convert.ToInt32("0"c), NumberBase)
    End Sub

    Public Sub New(BaseXNumber As String, NumberBaseLow As Integer, NumberBaseHigh As Integer)
        _BaseXNumber = BaseXNumber
        Me.NumberBaseLow = NumberBaseLow
        Me.NumberBaseHigh = NumberBaseHigh
    End Sub

    Public Sub New(Base10Number As Double)
        _Base10Number = Base10Number
    End Sub

    Private Sub DetermineNumberBase()
        Dim highestValue As Integer

        Dim currentValue As Integer

        For Each value As Char In _BaseXNumber

            currentValue = Convert.ToInt32(value)
            If currentValue > highestValue Then
                highestValue = currentValue
            End If
        Next

        NumberBaseHigh = highestValue
        NumberBaseLow = Convert.ToInt32("0"c) 'assume 0 is the lowest

    End Sub

    Private Function ToBaseString() As String
        Dim Base10Number As Double = _Base10Number

        Dim intPart As Long = Math.Truncate(Base10Number)
        Dim fracPart As Long = (Base10Number - intPart).ToString.Replace(DecimalSeparator, "")

        Dim intPartString As String = ConvertIntToString(intPart)
        Dim fracPartString As String = If(fracPart <> 0, DecimalSeparator & ConvertIntToString(fracPart), "")

        Return intPartString & fracPartString

    End Function

    Private Function ToBase10() As Double
        Dim intPartString As String = _BaseXNumber.Split(DecimalSeparator)(0).Replace(GroupSeparator, "")
        Dim fracPartString As String = If(_BaseXNumber.Contains(DecimalSeparator), _BaseXNumber.Split(DecimalSeparator)(1), "")

        Dim intPart As Long = ConvertStringToInt(intPartString)
        Dim fracPartNumerator As Long = ConvertStringToInt(fracPartString)
        Dim fracPartDenominator As Long = ConvertStringToInt(GetEncodedChar(1) & String.Join("", Enumerable.Repeat(GetEncodedChar(0), fracPartString.ToString.Length)))

        Return Convert.ToDouble(intPart + fracPartNumerator / fracPartDenominator)

    End Function

    Private Function ConvertIntToString(ValueToConvert As Long) As String
        Dim result As String = String.Empty
        Dim targetBase As Long = GetEncodingCharsLength()

        Do
            result = GetEncodedChar(ValueToConvert Mod targetBase) & result
            ValueToConvert = ValueToConvert \ targetBase
        Loop While ValueToConvert > 0

        Return result
    End Function

    Private Function ConvertStringToInt(ValueToConvert As String) As Long
        Dim result As Long
        Dim targetBase As Integer = GetEncodingCharsLength()
        Dim startBase As Integer = GetEncodingCharsStartBase()

        Dim value As Char
        For x As Integer = 0 To ValueToConvert.Length - 1
            value = ValueToConvert(x)
            result += GetDecodedChar(value) * Convert.ToInt32(Math.Pow(GetEncodingCharsLength, ValueToConvert.Length - (x + 1)))
        Next

        Return result

    End Function

    Private Function GetEncodedChar(index As Integer) As Char
        If _CharacterArray IsNot Nothing AndAlso _CharacterArray.Count > 0 Then
            Return _CharacterArray(index)
        Else
            Return Convert.ToChar(index + NumberBaseLow)
        End If
    End Function

    Private Function GetDecodedChar(character As Char) As Integer
        If _CharacterArray IsNot Nothing AndAlso _CharacterArray.Count > 0 Then
            Return _CharacterArray.IndexOf(character)
        Else
            Return Convert.ToInt32(character) - NumberBaseLow
        End If
    End Function

    Private Function GetEncodingCharsLength() As Integer
        If _CharacterArray IsNot Nothing AndAlso _CharacterArray.Count > 0 Then
            Return _CharacterArray.Count
        Else
            Return NumberBaseHigh - NumberBaseLow + 1
        End If
    End Function

    Private Function GetEncodingCharsStartBase() As Integer
        If _CharacterArray IsNot Nothing AndAlso _CharacterArray.Count > 0 Then
            Return GetHighLow.Key
        Else
            Return NumberBaseLow
        End If
    End Function
End Class

And now for the code to loop through Excel columns:

    Public Function GetColumnList(DataSheetID As String) As List(Of String)
        Dim workingColumn As New BaseNumber("A")
        workingColumn.SetCharacterArray("@ABCDEFGHIJKLMNOPQRSTUVWXYZ")

        Dim listOfPopulatedColumns As New List(Of String)
        Dim countOfEmptyColumns As Integer

        Dim colHasData As Boolean
        Dim cellHasData As Boolean

        Do
            colHasData = True
            cellHasData = False
            For r As Integer = 1 To GetMaxRow(DataSheetID)
                cellHasData = cellHasData Or XLGetCellValue(DataSheetID, workingColumn.GetBaseXNumber & r) <> ""
            Next
            colHasData = colHasData And cellHasData

            'keep trying until we get 4 empty columns in a row
            If colHasData Then
                listOfPopulatedColumns.Add(workingColumn.GetBaseXNumber)
                countOfEmptyColumns = 0
            Else
                countOfEmptyColumns += 1
            End If

            'we are already starting with column A, so increment after we check column A
            Do
                workingColumn.SetNumber(workingColumn.GetBase10Number + 1)
            Loop Until Not workingColumn.GetBaseXNumber.Contains("@")

        Loop Until countOfEmptyColumns > 3

        Return listOfPopulatedColumns

    End Function

You'll note the important part of the Excel part is that 0 is identified by a @ in the re-based number. So I just filter out all the numbers that have an @ in them and I get the proper sequence (A, B, C, ..., Z, AA, AB, AC, ...).

Read XLSX file in Java

docx4j now covers xlsx as well.

"Why would you use docx4j to do this", I hear you ask, "rather than POI, which focuses on xlsx and binary xls?"

Probably because you like JAXB (as opposed to XML Beans), or you are already using docx4j for docx or pptx, and need to be able to do some stuff with xlsx as well.

Another possible reason is that the jar XML Beans generates from the OpenXML schemas is too big for your purposes. (To get around this, POI offers a 'lite' subset: the 'big' ooxml-schemas-1.0.jar is 14.5 MB! But if you need to support arbitrary spreadsheets, you'll probably need the complete jar). In contrast, the whole of docx4j/pptx4j/xlsx4j weighs in at about the same as POI's lite subset.

If you are processing spreadsheets only (ie not docx or pptx), and preceding paragraph is not a concern for you, then you would probably be best off using POI.

Difference between RUN and CMD in a Dockerfile

RUN is an image build step, the state of the container after a RUN command will be committed to the container image. A Dockerfile can have many RUN steps that layer on top of one another to build the image.

CMD is the command the container executes by default when you launch the built image. A Dockerfile will only use the final CMD defined. The CMD can be overridden when starting a container with docker run $image $other_command.

ENTRYPOINT is also closely related to CMD and can modify the way a container starts an image.

How do you monitor network traffic on the iPhone?

You didnt specify the platform you use, so I assume it's a Mac ;-)

What I do is use a proxy. I use SquidMan, a standalone implementation of Squid

I start SquidMan on the Mac, then on the iPhone I enter the Proxy params in the General/Wifi Settings.

Then I can watch the HTTP trafic in the Console App, looking at the squid-access.log

If I need more infos, I switch to tcpdump, but I suppose WireShark should work too.

Adding a css class to select using @Html.DropDownList()

There are some options in constructors look, if you don't have dropdownList and you wanna insert CSS class you can use like

@Html.DropDownList("Country", null, "Choose-Category", new {@class="form-control"})

in this case Country is the name of your dropdown, null is for you aren't passing any generic list from your controller "Choose-Category" is selected item and last one in CSS class if you don't wanna select any default option so simple replace "Choose-Category" with ""

disable past dates on datepicker

Give zero to mindate and it'll disabale past dates.

$( "#datepicker" ).datepicker({ minDate: 0});

here is a Live fiddle working example http://jsfiddle.net/mayooresan/ZL2Bc/

The official documentation is available here

How do I space out the child elements of a StackPanel?

The UniformGrid might not be available in Silverlight, but someone has ported it from WPF. http://www.jeff.wilcox.name/2009/01/uniform-grid/

PHP write file from input to txt

use fwrite() instead of file_put_contents()

Center image in div horizontally

I think its better to to do text-align center for div and let image take care of the height. Just specify a top and bottom padding for div to have space between image and div. Look at this example: http://jsfiddle.net/Tv9mG/

Can HTML be embedded inside PHP "if" statement?

<?php if($condition) : ?>
    <a href="http://yahoo.com">This will only display if $condition is true</a>
<?php endif; ?>

By request, here's elseif and else (which you can also find in the docs)

<?php if($condition) : ?>
    <a href="http://yahoo.com">This will only display if $condition is true</a>
<?php elseif($anotherCondition) : ?>
    more html
<?php else : ?>
    even more html
<?php endif; ?>

It's that simple.

The HTML will only be displayed if the condition is satisfied.

When do you use POST and when do you use GET?

Well one major thing is anything you submit over GET is going to be exposed via the URL. Secondly as Ceejayoz says, there is a limit on characters for a URL.

When adding a Javascript library, Chrome complains about a missing source map, why?

I get this warning in Angular if I run:

ng serve --sourceMap=false

To fix:

ng serve

How to read values from the querystring with ASP.NET Core?

You could use the ToString method on IQueryCollection which will return the desired value if a single page parameter is specified:

string page = HttpContext.Request.Query["page"].ToString();

if there are multiple values like ?page=1&page=2 then the result of the ToString call will be 1,2

But as @mike-g suggested in his answer you would better use model binding and not directly accessing the HttpContext.Request.Query object.

Django, creating a custom 500/404 error page

Official answer:

Here is the link to the official documentation on how to set up custom error views:

https://docs.djangoproject.com/en/stable/topics/http/views/#customizing-error-views

It says to add lines like these in your URLconf (setting them anywhere else will have no effect):

handler404 = 'mysite.views.my_custom_page_not_found_view'
handler500 = 'mysite.views.my_custom_error_view'
handler403 = 'mysite.views.my_custom_permission_denied_view'
handler400 = 'mysite.views.my_custom_bad_request_view'

You can also customise the CSRF error view by modifying the setting CSRF_FAILURE_VIEW.

Default error handlers:

It's worth reading the documentation of the default error handlers, page_not_found, server_error, permission_denied and bad_request. By default, they use these templates if they can find them, respectively: 404.html, 500.html, 403.html, and 400.html.

So if all you want to do is make pretty error pages, just create those files in a TEMPLATE_DIRS directory, you don't need to edit URLConf at all. Read the documentation to see which context variables are available.

In Django 1.10 and later, the default CSRF error view uses the template 403_csrf.html.

Gotcha:

Don't forget that DEBUG must be set to False for these to work, otherwise, the normal debug handlers will be used.

'POCO' definition

Interesting. The only thing I knew that had to do with programming and had POCO in it is the POCO C++ framework.

R for loop skip to next iteration ifelse

for(n in 1:5) {
  if(n==3) next # skip 3rd iteration and go to next iteration
  cat(n)
}

Where is android studio building my .apk file?

Take a look at this question.

TL;DR: clean, then build.

./gradlew clean packageDebug 

How can I get the DateTime for the start of the week?

Let's combine the culture-safe answer and the extension method answer:

public static class DateTimeExtensions
{
    public static DateTime StartOfWeek(this DateTime dt, DayOfWeek startOfWeek)
    {
        System.Globalization.CultureInfo ci = System.Threading.Thread.CurrentThread.CurrentCulture;
        DayOfWeek fdow = ci.DateTimeFormat.FirstDayOfWeek;
        return DateTime.Today.AddDays(-(DateTime.Today.DayOfWeek- fdow));
    }
}

If else in stored procedure sql server

if not exists (select dist_id from tbl_stock where dist_id= @cust_id and item_id=@item_id)
    insert into tbl_stock(dist_id,item_id,qty)values(@cust_id, @item_id, @qty); 
else
    update tbl_stock set qty=(qty + @qty) where dist_id= @cust_id and item_id= @item_id;

Throwing exceptions in a PHP Try Catch block

function _modulename_getData($field, $table) {
  try {
    if (empty($field)) {
      throw new Exception("The field is undefined."); 
    }
    // rest of code here...
  }
  catch (Exception $e) {
    /*
        Here you can either echo the exception message like: 
        echo $e->getMessage(); 

        Or you can throw the Exception Object $e like:
        throw $e;
    */
  }
}

SSH -L connection successful, but localhost port forwarding not working "channel 3: open failed: connect failed: Connection refused"

I had this problem when I wanted to make a vnc connection via a tunnel. But the vncserver was not running. I solved it by opening the channel on the remote machine with vncserver :3.

Using "word-wrap: break-word" within a table

table-layout: fixed will get force the cells to fit the table (and not the other way around), e.g.:

<table style="border: 1px solid black; width: 100%; word-wrap:break-word;
              table-layout: fixed;">
  <tr>
    <td>
        aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
        bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
    </td>
  </tr>
</table>

Check file size before upload

I created a jQuery version of PhpMyCoder's answer:

$('form').submit(function( e ) {    
    if(!($('#file')[0].files[0].size < 10485760 && get_extension($('#file').val()) == 'jpg')) { // 10 MB (this size is in bytes)
        //Prevent default and display error
        alert("File is wrong type or over 10Mb in size!");
        e.preventDefault();
    }
});

function get_extension(filename) {
    return filename.split('.').pop().toLowerCase();
}

How to solve javax.net.ssl.SSLHandshakeException Error?

Whenever we are trying to connect to URL,

if server at the other site is running on https protocol and is mandating that we should communicate via information provided in certificate then we have following option:

1) ask for the certificate(download the certificate), import this certificate in trustore. Default trustore java uses can be found in \Java\jdk1.6.0_29\jre\lib\security\cacerts, then if we retry to connect to the URL connection would be accepted.

2) In normal business cases, we might be connecting to internal URLS in organizations and we know that they are correct. In such cases, you trust that it is the correct URL, In such cases above, code can be used which will not mandate to store the certificate to connect to particular URL.

for the point no 2 we have to follow below steps :

1) write below method which sets HostnameVerifier for HttpsURLConnection which returns true for all cases meaning we are trusting the trustStore.

  // trusting all certificate 
 public void doTrustToCertificates() throws Exception {
        Security.addProvider(new com.sun.net.ssl.internal.ssl.Provider());
        TrustManager[] trustAllCerts = new TrustManager[]{
                new X509TrustManager() {
                    public X509Certificate[] getAcceptedIssuers() {
                        return null;
                    }

                    public void checkServerTrusted(X509Certificate[] certs, String authType) throws CertificateException {
                        return;
                    }

                    public void checkClientTrusted(X509Certificate[] certs, String authType) throws CertificateException {
                        return;
                    }
                }
        };

        SSLContext sc = SSLContext.getInstance("SSL");
        sc.init(null, trustAllCerts, new SecureRandom());
        HttpsURLConnection.setDefaultSSLSocketFactory(sc.getSocketFactory());
        HostnameVerifier hv = new HostnameVerifier() {
            public boolean verify(String urlHostName, SSLSession session) {
                if (!urlHostName.equalsIgnoreCase(session.getPeerHost())) {
                    System.out.println("Warning: URL host '" + urlHostName + "' is different to SSLSession host '" + session.getPeerHost() + "'.");
                }
                return true;
            }
        };
        HttpsURLConnection.setDefaultHostnameVerifier(hv);
    }

2) write below method, which calls doTrustToCertificates before trying to connect to URL

    // connecting to URL
    public void connectToUrl(){
     doTrustToCertificates();//  
     URL url = new URL("https://www.example.com");
     HttpURLConnection conn = (HttpURLConnection)url.openConnection(); 
     System.out.println("ResponseCode ="+conn.getResponseCode());
   }

This call will return response code = 200 means connection is successful.

For more detail and sample example you can refer to URL.

Convenient C++ struct initialisation

For me the laziest way to allow inline inizialization is use this macro.

#define METHOD_MEMBER(TYPE, NAME, CLASS) \
CLASS &set_ ## NAME(const TYPE &_val) { NAME = _val; return *this; } \
TYPE NAME;

struct foo {
    METHOD_MEMBER(string, attr1, foo)
    METHOD_MEMBER(int, attr2, foo)
    METHOD_MEMBER(double, attr3, foo)
};

// inline usage
foo test = foo().set_attr1("hi").set_attr2(22).set_attr3(3.14);

That macro create attribute and self reference method.

how to display a javascript var in html body

<html>
<head>
<script type="text/javascript">
var number = 123;
var string = "abcd";

function docWrite(variable) {
    document.write(variable);
}
</script>
</head>

<body>
<h1>the value for number is: <script>docWrite(number)</script></h1>

<h2>the text is: <script>docWrite(string)</script> </h2>
</body>
</html>

You can shorten document.write but can't avoid <script> tag

Get first key in a (possibly) associative array?

You can play with your array

$daysArray = array('Monday', 'Tuesday', 'Sunday');
$day = current($transport); // $day = 'Monday';
$day = next($transport);    // $day = 'Tuesday';
$day = current($transport); // $day = 'Tuesday';
$day = prev($transport);    // $day = 'Monday';
$day = end($transport);     // $day = 'Sunday';
$day = current($transport); // $day = 'Sunday';

To get the first element of array you can use current and for last element you can use end

Edit

Just for the sake for not getting any more down votes for the answer you can convert you key to value using array_keys and use as shown above.

How Big can a Python List Get?

As the Python documentation says:

sys.maxsize

The largest positive integer supported by the platform’s Py_ssize_t type, and thus the maximum size lists, strings, dicts, and many other containers can have.

In my computer (Linux x86_64):

>>> import sys
>>> print sys.maxsize
9223372036854775807

Tests not running in Test Explorer

enter image description here

Setting Processor Architecture for AnyCPU Projects in Test Explorer fixed my issue! See screenshot above.

Get current rowIndex of table in jQuery

Since "$(this).parent().index();" and "$(this).parent('table').index();" don't work for me, I use this code instead:

$('td').click(function(){
   var row_index = $(this).closest("tr").index();
   var col_index = $(this).index();
});

Bootstrap Carousel Full Screen

I'm had the same problem, and I tried with the answers above, but I wanted something more thin, then I tried to change one by one opsions, and discover that we just need to add

.carousel {
  height: 100%;
}

Vector of structs initialization

After looking on the accepted answer I realized that if know size of required vector then we have to use a loop to initialize every element

But I found new to do this using default_structure_element like following...

#include <bits/stdc++.h>
typedef long long ll;
using namespace std;

typedef struct subject {
  string name;
  int marks;
  int credits;
}subject;

int main(){
  subject default_subject;
  default_subject.name="NONE";
  default_subject.marks = 0;
  default_subject.credits = 0;

  vector <subject> sub(10,default_subject);         // default_subject to initialize

  //to check is it initialised
  for(ll i=0;i<sub.size();i++) {
    cout << sub[i].name << " " << sub[i].marks << " " << sub[i].credits << endl;
  } 
}

Then I think its good to way to initialize a vector of the struct, isn't it?

Using grep to search for hex strings in a file

There's also a pretty handy tool called binwalk, written in python, which provides for binary pattern matching (and quite a lot more besides). Here's how you would search for a binary string, which outputs the offset in decimal and hex (from the docs):

$ binwalk -R "\x00\x01\x02\x03\x04" firmware.bin
DECIMAL     HEX         DESCRIPTION
--------------------------------------------------------------------------
377654      0x5C336     Raw string signature

ExecuteReader requires an open and available Connection. The connection's current state is Connecting

Sorry for only commenting in the first place, but i'm posting almost every day a similar comment since many people think that it would be smart to encapsulate ADO.NET functionality into a DB-Class(me too 10 years ago). Mostly they decide to use static/shared objects since it seems to be faster than to create a new object for any action.

That is neither a good idea in terms of peformance nor in terms of fail-safety.

Don't poach on the Connection-Pool's territory

There's a good reason why ADO.NET internally manages the underlying Connections to the DBMS in the ADO-NET Connection-Pool:

In practice, most applications use only one or a few different configurations for connections. This means that during application execution, many identical connections will be repeatedly opened and closed. To minimize the cost of opening connections, ADO.NET uses an optimization technique called connection pooling.

Connection pooling reduces the number of times that new connections must be opened. The pooler maintains ownership of the physical connection. It manages connections by keeping alive a set of active connections for each given connection configuration. Whenever a user calls Open on a connection, the pooler looks for an available connection in the pool. If a pooled connection is available, it returns it to the caller instead of opening a new connection. When the application calls Close on the connection, the pooler returns it to the pooled set of active connections instead of closing it. Once the connection is returned to the pool, it is ready to be reused on the next Open call.

So obviously there's no reason to avoid creating,opening or closing connections since actually they aren't created,opened and closed at all. This is "only" a flag for the connection pool to know when a connection can be reused or not. But it's a very important flag, because if a connection is "in use"(the connection pool assumes), a new physical connection must be openend to the DBMS what is very expensive.

So you're gaining no performance improvement but the opposite. If the maximum pool size specified (100 is the default) is reached, you would even get exceptions(too many open connections ...). So this will not only impact the performance tremendously but also be a source for nasty errors and (without using Transactions) a data-dumping-area.

If you're even using static connections you're creating a lock for every thread trying to access this object. ASP.NET is a multithreading environment by nature. So theres a great chance for these locks which causes performance issues at best. Actually sooner or later you'll get many different exceptions(like your ExecuteReader requires an open and available Connection).

Conclusion:

  • Don't reuse connections or any ADO.NET objects at all.
  • Don't make them static/shared(in VB.NET)
  • Always create, open(in case of Connections), use, close and dispose them where you need them(f.e. in a method)
  • use the using-statement to dispose and close(in case of Connections) implicitely

That's true not only for Connections(although most noticable). Every object implementing IDisposable should be disposed(simplest by using-statement), all the more in the System.Data.SqlClient namespace.

All the above speaks against a custom DB-Class which encapsulates and reuse all objects. That's the reason why i commented to trash it. That's only a problem source.


Edit: Here's a possible implementation of your retrievePromotion-method:

public Promotion retrievePromotion(int promotionID)
{
    Promotion promo = null;
    var connectionString = System.Configuration.ConfigurationManager.ConnectionStrings["MainConnStr"].ConnectionString;
    using (SqlConnection connection = new SqlConnection(connectionString))
    {
        var queryString = "SELECT PromotionID, PromotionTitle, PromotionURL FROM Promotion WHERE PromotionID=@PromotionID";
        using (var da = new SqlDataAdapter(queryString, connection))
        {
            // you could also use a SqlDataReader instead
            // note that a DataTable does not need to be disposed since it does not implement IDisposable
            var tblPromotion = new DataTable();
            // avoid SQL-Injection
            da.SelectCommand.Parameters.Add("@PromotionID", SqlDbType.Int);
            da.SelectCommand.Parameters["@PromotionID"].Value = promotionID;
            try
            {
                connection.Open(); // not necessarily needed in this case because DataAdapter.Fill does it otherwise 
                da.Fill(tblPromotion);
                if (tblPromotion.Rows.Count != 0)
                {
                    var promoRow = tblPromotion.Rows[0];
                    promo = new Promotion()
                    {
                        promotionID    = promotionID,
                        promotionTitle = promoRow.Field<String>("PromotionTitle"),
                        promotionUrl   = promoRow.Field<String>("PromotionURL")
                    };
                }
            }
            catch (Exception ex)
            {
                // log this exception or throw it up the StackTrace
                // we do not need a finally-block to close the connection since it will be closed implicitely in an using-statement
                throw;
            }
        }
    }
    return promo;
}

UTF-8 text is garbled when form is posted as multipart/form-data

I had the same problem using Apache commons-fileupload. I did not find out what causes the problems especially because I have the UTF-8 encoding in the following places: 1. HTML meta tag 2. Form accept-charset attribute 3. Tomcat filter on every request that sets the "UTF-8" encoding

-> My solution was to especially convert Strings from ISO-8859-1 (or whatever is the default encoding of your platform) to UTF-8:

new String (s.getBytes ("iso-8859-1"), "UTF-8");

hope that helps

Edit: starting with Java 7 you can also use the following:

new String (s.getBytes (StandardCharsets.ISO_8859_1), StandardCharsets.UTF_8);

PHP json_encode json_decode UTF-8

  header('Content-Type: application/json; charset=utf-8');

Android open camera from button

For me this worked perfectly fine .

 Intent intent=new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
 startActivity(intent);

and add this permission to mainfest file:

<uses-permission android:name="android.permission.CAMERA">

It opens the camera,after capturing the image it saves the image to gallery with a new image set.

Detect if a Form Control option button is selected in VBA

If you are using a Form Control, you can get the same property as ActiveX by using OLEFormat.Object property of the Shape Object. Better yet assign it in a variable declared as OptionButton to get the Intellisense kick in.

Dim opt As OptionButton

With Sheets("Sheet1") ' Try to be always explicit
    Set opt = .Shapes("Option Button 1").OLEFormat.Object ' Form Control
    Debug.Pring opt.Value ' returns 1 (true) or -4146 (false)
End With

But then again, you really don't need to know the value.
If you use Form Control, you associate a Macro or sub routine with it which is executed when it is selected. So you just need to set up a sub routine that identifies which button is clicked and then execute a corresponding action for it.

For example you have 2 Form Control Option Buttons.

Sub CheckOptions()
    Select Case Application.Caller
    Case "Option Button 1"
    ' Action for option button 1
    Case "Option Button 2"
    ' Action for option button 2
    End Select
End Sub

In above code, you have only one sub routine assigned to both option buttons.
Then you test which called the sub routine by checking Application.Caller.
This way, no need to check whether the option button value is true or false.

NotificationCenter issue on Swift 3

Notifications appear to have changed again (October 2016).

// Register to receive notification

NotificationCenter.default.addObserver(self, selector: #selector(yourClass.yourMethod), name: NSNotification.Name(rawValue: "yourNotificatioName"), object: nil)

// Post notification

NotificationCenter.default.post(name: NSNotification.Name(rawValue: "yourNotificationName"), object: nil)

Why is there no tuple comprehension in Python?

You can use a generator expression:

tuple(i for i in (1, 2, 3))

but parentheses were already taken for … generator expressions.

Jquery : Refresh/Reload the page on clicking a button

You can also use window.location.href=window.location.href;

How can I put a ListView into a ScrollView without it collapsing?

You Create Custom ListView Which is non Scrollable

public class NonScrollListView extends ListView {

    public NonScrollListView(Context context) {
        super(context);
    }
    public NonScrollListView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }
    public NonScrollListView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }
    @Override
    public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
            int heightMeasureSpec_custom = MeasureSpec.makeMeasureSpec(
                    Integer.MAX_VALUE >> 2, MeasureSpec.AT_MOST);
            super.onMeasure(widthMeasureSpec, heightMeasureSpec_custom);
            ViewGroup.LayoutParams params = getLayoutParams();
            params.height = getMeasuredHeight();    
    }
}

In Your Layout Resources File

<RelativeLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content" >

    <!-- com.Example Changed with your Package name -->

    <com.Example.NonScrollListView
        android:id="@+id/lv_nonscroll_list"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >
    </com.Example.NonScrollListView>

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@+id/lv_nonscroll_list" >

        <!-- Your another layout in scroll view -->

    </RelativeLayout>
</RelativeLayout>

In Java File

Create a object of your customListview instead of ListView like : NonScrollListView non_scroll_list = (NonScrollListView) findViewById(R.id.lv_nonscroll_list);

Android ListView headers

Here is a sample project, based on antew's detailed and helpful answer, that implements a ListView with multiple headers that incorporates view holders to improve scrolling performance.

In this project, the objects represented in the ListView are instances of either the class HeaderItem or the class RowItem, both of which are subclasses of the abstract class Item. Each subclass of Item corresponds to a different view type in the custom adapter, ItemAdapter. The method getView() on ItemAdapter delegates the creation of the view for each list item to an individualized getView() method on either HeaderItem or RowItem, depending on the Item subclass used at the position passed to the getView() method on the adapter. Each Item subclass provides its own view holder.

The view holders are implemented as follows. The getView() methods on the Item subclasses check whether the View object that was passed to the getView() method on ItemAdapter is null. If so, the appropriate layout is inflated, and a view holder object is instantiated and associated with the inflated view via View.setTag(). If the View object is not null, then a view holder object was already associated with the view, and the view holder is retrieved via View.getTag(). The way in which the view holders are used can be seen in the following code snippet from HeaderItem:

@Override
View getView(LayoutInflater i, View v) {
    ViewHolder h;
    if (v == null) {
        v = i.inflate(R.layout.header, null);
        h = new ViewHolder(v);
        v.setTag(h);
    } else {
        h = (ViewHolder) v.getTag();
    }
    h.category.setText(text());
    return v;
}

private class ViewHolder {
    final TextView category;

    ViewHolder(View v) {
        category = v.findViewById(R.id.category);
    }
}

The complete implementation of the ListView follows. Here is the Java code:

import android.app.ListActivity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.TextView;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

public class MainActivity extends ListActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setListAdapter(new ItemAdapter(getItems()));
    }

    class ItemAdapter extends ArrayAdapter<Item> {
        final private List<Class<?>> viewTypes;

        ItemAdapter(List<Item> items) {
            super(MainActivity.this, 0, items);
            if (items.contains(null))
                throw new IllegalArgumentException("null item");
            viewTypes = getViewTypes(items);
        }

        private List<Class<?>> getViewTypes(List<Item> items) {
            Set<Class<?>> set = new HashSet<>();
            for (Item i : items) 
                set.add(i.getClass());
            List<Class<?>> list = new ArrayList<>(set);
            return Collections.unmodifiableList(list);
        }

        @Override
        public int getViewTypeCount() {
            return viewTypes.size();
        }

        @Override
        public int getItemViewType(int position) {
            Item t = getItem(position);
            return viewTypes.indexOf(t.getClass());
        }

        @Override
        public View getView(int position, View v, ViewGroup unused) {
            return getItem(position).getView(getLayoutInflater(), v);
        }
    }

    abstract private class Item {
        final private String text;

        Item(String text) {
            this.text = text;
        }

        String text() { return text; }

        abstract View getView(LayoutInflater i, View v);
    }

    private class HeaderItem extends Item {
        HeaderItem(String text) {
            super(text);
        }

        @Override
        View getView(LayoutInflater i, View v) {
            ViewHolder h;
            if (v == null) {
                v = i.inflate(R.layout.header, null);
                h = new ViewHolder(v);
                v.setTag(h);
            } else {
                h = (ViewHolder) v.getTag();
            }
            h.category.setText(text());
            return v;
        }

        private class ViewHolder {
            final TextView category;

            ViewHolder(View v) {
                category = v.findViewById(R.id.category);
            }
        }
    }

    private class RowItem extends Item {
        RowItem(String text) {
            super(text);
        }

        @Override
        View getView(LayoutInflater i, View v) {
            ViewHolder h;
            if (v == null) {
                v = i.inflate(R.layout.row, null);
                h = new ViewHolder(v);
                v.setTag(h);
            } else {
                h = (ViewHolder) v.getTag();
            }
            h.option.setText(text());
            return v;
        }

        private class ViewHolder {
            final TextView option;

            ViewHolder(View v) {
                option = v.findViewById(R.id.option);
            }
        }
    }

    private List<Item> getItems() {
        List<Item> t = new ArrayList<>();
        t.add(new HeaderItem("Header 1"));
        t.add(new RowItem("Row 2"));
        t.add(new HeaderItem("Header 3"));
        t.add(new RowItem("Row 4"));

        t.add(new HeaderItem("Header 5"));
        t.add(new RowItem("Row 6"));
        t.add(new HeaderItem("Header 7"));
        t.add(new RowItem("Row 8"));

        t.add(new HeaderItem("Header 9"));
        t.add(new RowItem("Row 10"));
        t.add(new HeaderItem("Header 11"));
        t.add(new RowItem("Row 12"));

        t.add(new HeaderItem("Header 13"));
        t.add(new RowItem("Row 14"));
        t.add(new HeaderItem("Header 15"));
        t.add(new RowItem("Row 16"));

        t.add(new HeaderItem("Header 17"));
        t.add(new RowItem("Row 18"));
        t.add(new HeaderItem("Header 19"));
        t.add(new RowItem("Row 20"));

        t.add(new HeaderItem("Header 21"));
        t.add(new RowItem("Row 22"));
        t.add(new HeaderItem("Header 23"));
        t.add(new RowItem("Row 24"));

        t.add(new HeaderItem("Header 25"));
        t.add(new RowItem("Row 26"));
        t.add(new HeaderItem("Header 27"));
        t.add(new RowItem("Row 28"));
        t.add(new RowItem("Row 29"));
        t.add(new RowItem("Row 30"));

        t.add(new HeaderItem("Header 31"));
        t.add(new RowItem("Row 32"));
        t.add(new HeaderItem("Header 33"));
        t.add(new RowItem("Row 34"));
        t.add(new RowItem("Row 35"));
        t.add(new RowItem("Row 36"));

        return t;
    }

}

There are also two list item layouts, one for each Item subclass. Here is the layout header, used by HeaderItem:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="#FFAAAAAA"
    >
    <TextView
        android:id="@+id/category"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_margin="4dp"
        android:textColor="#FF000000"
        android:textSize="20sp"
        android:textStyle="bold"
        />
 </LinearLayout>

And here is the layout row, used by RowItem:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:minHeight="?android:attr/listPreferredItemHeight"
    >
    <TextView
        android:id="@+id/option"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="15sp"
        />
</LinearLayout>

Here is an image of a portion of the resulting ListView:

ListView with multiple headers

java.net.ConnectException: Connection refused

I had the same problem, but running the Server before running the Client fixed it.

Iterating through a golang map

For example,

package main

import "fmt"

func main() {
    type Map1 map[string]interface{}
    type Map2 map[string]int
    m := Map1{"foo": Map2{"first": 1}, "boo": Map2{"second": 2}}
    //m = map[foo:map[first: 1] boo: map[second: 2]]
    fmt.Println("m:", m)
    for k, v := range m {
        fmt.Println("k:", k, "v:", v)
    }
}

Output:

m: map[boo:map[second:2] foo:map[first:1]]
k: boo v: map[second:2]
k: foo v: map[first:1]

Meaning of = delete after function declaration

Deleting a function is a C++11 feature:

The common idiom of "prohibiting copying" can now be expressed directly:

class X {
    // ...
    X& operator=(const X&) = delete;  // Disallow copying
    X(const X&) = delete;
};

[...]

The "delete" mechanism can be used for any function. For example, we can eliminate an undesired conversion like this:

struct Z {
    // ...

    Z(long long);     // can initialize with an long long         
    Z(long) = delete; // but not anything less
};

How can I take a screenshot with Selenium WebDriver?

Python

You can capture the image from windows using the Python web driver. Use the code below which page need to capture the screenshot.

driver.save_screenshot('c:\foldername\filename.extension(png, jpeg)')

How to include bootstrap css and js in reactjs app?

Just in case if you can use yarn which is recommended for React apps,

you can do,

yarn add [email protected] // this is to add bootstrap with a specific  version

This will add the bootstrap as a dependency to your package.json as well.

{
  "name": "my-app",
  "version": "0.1.0",
  "private": true,
  "dependencies": {
    "bootstrap": "4.1.1", // it will add an entry here
    "react": "^16.5.2",
    "react-dom": "^16.5.2",
    "react-scripts": "1.1.5"
  },
  "scripts": {
    "start": "react-scripts start",
    "build": "react-scripts build",
    "test": "react-scripts test --env=jsdom",
    "eject": "react-scripts eject"
  }
}

After that just import bootstrap in your index.js file.

import 'bootstrap/dist/css/bootstrap.css';

Change background color on mouseover and remove it after mouseout

Set the original background-color in you CSS file:

.forum{
    background-color:#f0f;
}?

You don't have to capture the original color in jQuery. Remember that jQuery will alter the style INLINE, so by setting the background-color to null you will get the same result.

$(function() {
    $(".forum").hover(
    function() {
        $(this).css('background-color', '#ff0')
    }, function() {
        $(this).css('background-color', '')
    });
});?

Parse XML using JavaScript

The following will parse an XML string into an XML document in all major browsers, including Internet Explorer 6. Once you have that, you can use the usual DOM traversal methods/properties such as childNodes and getElementsByTagName() to get the nodes you want.

var parseXml;
if (typeof window.DOMParser != "undefined") {
    parseXml = function(xmlStr) {
        return ( new window.DOMParser() ).parseFromString(xmlStr, "text/xml");
    };
} else if (typeof window.ActiveXObject != "undefined" &&
       new window.ActiveXObject("Microsoft.XMLDOM")) {
    parseXml = function(xmlStr) {
        var xmlDoc = new window.ActiveXObject("Microsoft.XMLDOM");
        xmlDoc.async = "false";
        xmlDoc.loadXML(xmlStr);
        return xmlDoc;
    };
} else {
    throw new Error("No XML parser found");
}

Example usage:

var xml = parseXml("<foo>Stuff</foo>");
alert(xml.documentElement.nodeName);

Which I got from https://stackoverflow.com/a/8412989/1232175.

SSL: CERTIFICATE_VERIFY_FAILED with Python3

In my case, I used the ssl module to "workaround" the certification like so:

import ssl

ssl._create_default_https_context = ssl._create_unverified_context

Then to read your link content, you can use:

urllib.request.urlopen(urllink)

C++ compiling on Windows and Linux: ifdef switch

It depends on the compiler. If you compile with, say, G++ on Linux and VC++ on Windows, this will do :

#ifdef linux
    ...
#elif _WIN32
    ...
#else
    ...
#endif

How to create a custom navigation drawer in android

I used below layout and able to achieve custom layout in Navigation View.

<android.support.design.widget.NavigationView
        android:id="@+id/navi_view"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="start|top"
        android:background="@color/navigation_view_bg_color"
        app:theme="@style/NavDrawerTextStyle">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:orientation="vertical">

            <include layout="@layout/drawer_header" />

            <include layout="@layout/navigation_drawer_menu" />
        </LinearLayout>
</android.support.design.widget.NavigationView> 

Add an object to a python list

while you should show how your code looks like that gives the problem, i think this scenario is very common. See copy/deepcopy

Moment.js with Vuejs

global members are not available by default in your <template>'s scope. But you can easily pass them on using computed properties.

computed: {
  moment: () => moment,
  console: () => console,
  window: () => window
}

Now you can use any of them in your template. i.e: console.log(moment(), window).

Note this doesn't add any overhead.

How do I return clean JSON from a WCF Service?

If you want nice json without hardcoding attributes into your service classes,

use <webHttp defaultOutgoingResponseFormat="Json"/> in your behavior config

Command not found when using sudo

Ok this is my solution: in ~/.bash_aliases just add the following:

# ADDS MY PATH WHEN SET AS ROOT
if [ $(id -u) = "0" ]; then
   export PATH=$PATH:/home/your_user/bin 
fi

Voila! Now you can execute your own scripts with sudo or set as ROOT without having to do an export PATH=$PATH:/home/your_user/bin everytime.

Notice that I need to be explicit when adding my PATH since HOME for superuser is /root

Get filename and path from URI from mediastore

After getting an image from the gallery, just pass the URI in the below method only for Android 4.4 (KitKat):

public String getPath(Uri contentUri) {// Will return "image:x*"

    String wholeID = DocumentsContract.getDocumentId(contentUri);

    // Split at colon, use second item in the array
    String id = wholeID.split(":")[1];

    String[] column = { MediaStore.Images.Media.DATA };

    // Where id is equal to
    String sel = MediaStore.Images.Media._ID + "=?";

    Cursor cursor = getContentResolver().query(
            MediaStore.Images.Media.EXTERNAL_CONTENT_URI, column, sel,
            new String[] { id }, null);

    String filePath = "";

    int columnIndex = cursor.getColumnIndex(column[0]);

    if (cursor.moveToFirst()) {
        filePath = cursor.getString(columnIndex);
    }

    cursor.close();
    return filePath;
}

Type Checking: typeof, GetType, or is?

1.

Type t = typeof(obj1);
if (t == typeof(int))

This is illegal, because typeof only works on types, not on variables. I assume obj1 is a variable. So, in this way typeof is static, and does its work at compile time instead of runtime.

2.

if (obj1.GetType() == typeof(int))

This is true if obj1 is exactly of type int. If obj1 derives from int, the if condition will be false.

3.

if (obj1 is int)

This is true if obj1 is an int, or if it derives from a class called int, or if it implements an interface called int.

How to elegantly check if a number is within a range?

As others said, use a simple if.

You should think about the ordering.

e.g

1 <= x && x <= 100

is easier to read than

x >= 1 && x <= 100

How do I remove the height style from a DIV using jQuery?

just to add to the answers here, I was using the height as a function with two options either specify the height if it is less than the window height, or set it back to auto

var windowHeight = $(window).height();
$('div#someDiv').height(function(){
    if ($(this).height() < windowHeight)
        return windowHeight;
    return 'auto';
});

I needed to center the content vertically if it was smaller than the window height or else let it scroll naturally so this is what I came up with

Stretch horizontal ul to fit width of div

People hate on tables for non-tabular data, but what you're asking for is exactly what tables are good at. <table width="100%">

How to create unit tests easily in eclipse

To create a test case template:

"New" -> "JUnit Test Case" -> Select "Class under test" -> Select "Available methods". I think the wizard is quite easy for you.

Javascript negative number

In ES6 you can use Math.sign function to determine if,

1. its +ve no
2. its -ve no
3. its zero (0)
4. its NaN


console.log(Math.sign(1))        // prints 1 
console.log(Math.sign(-1))       // prints -1
console.log(Math.sign(0))        // prints 0
console.log(Math.sign("abcd"))   // prints NaN

Finding element's position relative to the document

For those that want to get the x and y coordinates of various positions of an element, relative to the document.

const getCoords = (element, position) => {
  const { top, left, width, height } = element.getBoundingClientRect();
  let point;
  switch (position) {
    case "top left":
      point = {
        x: left + window.pageXOffset,
        y: top + window.pageYOffset
      };
      break;
    case "top center":
      point = {
        x: left + width / 2 + window.pageXOffset,
        y: top + window.pageYOffset
      };
      break;
    case "top right":
      point = {
        x: left + width + window.pageXOffset,
        y: top + window.pageYOffset
      };
      break;
    case "center left":
      point = {
        x: left + window.pageXOffset,
        y: top + height / 2 + window.pageYOffset
      };
      break;
    case "center":
      point = {
        x: left + width / 2 + window.pageXOffset,
        y: top + height / 2 + window.pageYOffset
      };
      break;
    case "center right":
      point = {
        x: left + width + window.pageXOffset,
        y: top + height / 2 + window.pageYOffset
      };
      break;
    case "bottom left":
      point = {
        x: left + window.pageXOffset,
        y: top + height + window.pageYOffset
      };
      break;
    case "bottom center":
      point = {
        x: left + width / 2 + window.pageXOffset,
        y: top + height + window.pageYOffset
      };
      break;
    case "bottom right":
      point = {
        x: left + width + window.pageXOffset,
        y: top + height + window.pageYOffset
      };
      break;
  }
  return point;
};

Usage

  • getCoords(document.querySelector('selector'), 'center')

  • getCoords(document.querySelector('selector'), 'bottom right')

  • getCoords(document.querySelector('selector'), 'top center')

Expanding a parent <div> to the height of its children

I made a parent div expand around content of a child div by having the child div as a single column that does not have any positioning attribute such as absolute specified.

Example:

#wrap {width:400px;padding:10px 200px 10px 200px;position:relative;margin:0px auto;}
#maincolumn {width:400px;}

Based on maincolumn div being the deepest child div of #wrap this defines the depth of the #wrap div and the 200px padding on either side creates two big blank columns for you to place absolutely positioned divs in as you please. You could even change the padding top and bottom to place header divs and footer divs using position:absolute.

How can I show dots ("...") in a span with hidden overflow?

Well, the "text-overflow: ellipsis" worked for me, but just if my limit was based on 'width', I has needed a solution that can be applied on lines ( on the'height' instead the 'width' ) so I did this script:

function listLimit (elm, line){
    var maxHeight = parseInt(elm.css('line-Height'))*line;

    while(elm.height() > maxHeight){
        var text = elm.text();
        elm.text(text.substring(0,text.length-10)).text(elm.text()+'...');
    }
}

And when I must, for example, that my h3 has only 2 lines I do :

$('h3').each(function(){
   listLimit ($(this), 2)
})

I dunno if that was the best practice for performance needs, but worked for me.

How to unmerge a Git merge?

git revert -m allows to un-merge still keeping the history of both merge and un-do operation. Might be good for documenting probably.

What is the best way to concatenate two vectors?

This is precisely what the member function std::vector::insert is for

std::vector<int> AB = A;
AB.insert(AB.end(), B.begin(), B.end());

Setting a WebRequest's body data

Update

See my other SO answer.


Original

var request = (HttpWebRequest)WebRequest.Create("https://example.com/endpoint");

string stringData = ""; // place body here
var data = Encoding.Default.GetBytes(stringData); // note: choose appropriate encoding

request.Method = "PUT";
request.ContentType = ""; // place MIME type here
request.ContentLength = data.Length;

var newStream = request.GetRequestStream(); // get a ref to the request body so it can be modified
newStream.Write(data, 0, data.Length);
newStream.Close();

CSS: fixed to bottom and centered

You should use a sticky footer solution such as this one :

* {
    margin: 0;
}
html, body {
    height: 100%;
}
.wrapper {
    min-height: 100%;
    height: auto !important;
    height: 100%;
    margin: 0 auto -142px; /* the bottom margin is the negative value of the footer's height */
}
.footer, .push {
    height: 142px; /* .push must be the same height as .footer */
}

There are others like this;

* {margin:0;padding:0;} 

/* must declare 0 margins on everything, also for main layout components use padding, not 
vertical margins (top and bottom) to add spacing, else those margins get added to total height 
and your footer gets pushed down a bit more, creating vertical scroll bars in the browser */

html, body, #wrap {height: 100%;}

body > #wrap {height: auto; min-height: 100%;}

#main {padding-bottom: 150px;}  /* must be same height as the footer */

#footer {position: relative;
    margin-top: -150px; /* negative value of footer height */
    height: 150px;
    clear:both;} 

/* CLEAR FIX*/
.clearfix:after {content: ".";
    display: block;
    height: 0;
    clear: both;
    visibility: hidden;}
.clearfix {display: inline-block;}
/* Hides from IE-mac \*/
* html .clearfix { height: 1%;}
.clearfix {display: block;}

with the html:

<div id="wrap">

    <div id="main" class="clearfix">

    </div>

</div>

<div id="footer">

</div>

Room - Schema export directory is not provided to the annotation processor so we cannot export the schema

@mikejonesguy answer is perfect, just in case you plan to test room migrations (recommended), add the schema location to the source sets.

In your build.gradle file you specify a folder to place these generated schema JSON files. As you update your schema, you’ll end up with several JSON files, one for every version. Make sure you commit every generated file to source control. The next time you increase your version number again, Room will be able to use the JSON file for testing.

build.gradle

android {

    // [...]

    defaultConfig {

        // [...]

        javaCompileOptions {
            annotationProcessorOptions {
                arguments = ["room.schemaLocation": "$projectDir/schemas".toString()]
            }
        }
    }

    // add the schema location to the source sets
    // used by Room, to test migrations
    sourceSets {
        androidTest.assets.srcDirs += files("$projectDir/schemas".toString())
    }

    // [...]
}

javascript regex for password containing at least 8 characters, 1 number, 1 upper and 1 lowercase

Your regular expression should look like:

/^(?=.*\d)(?=.*[a-z])(?=.*[A-Z])[0-9a-zA-Z]{8,}$/

Here is an explanation:

/^
  (?=.*\d)          // should contain at least one digit
  (?=.*[a-z])       // should contain at least one lower case
  (?=.*[A-Z])       // should contain at least one upper case
  [a-zA-Z0-9]{8,}   // should contain at least 8 from the mentioned characters
$/

How do I change a tab background color when using TabLayout?

You can try this:

<style name="MyCustomTabLayout" parent="Widget.Design.TabLayout">
    <item name="tabBackground">@drawable/background</item>
</style>

In your background xml file:

<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_selected="true" android:drawable="@color/white" />
    <item android:drawable="@color/black" />
</selector>

How to output a multiline string in Bash?

One more thing, using printf with predefined var as template.

msg="First line %s
Second line %s
Third line %s
"

one='additional message for the first line'
two='2'
tri='this is the last one'

printf "$msg" "$one" "$two" "$tri"

This ^^^ will print whole message with additional vars inserted instead of '%s' in provided order.

xml.LoadData - Data at the root level is invalid. Line 1, position 1

Main culprit for this error is logic which determines encoding when converting Stream or byte[] array to .NET string.

Using StreamReader created with 2nd constructor parameter detectEncodingFromByteOrderMarks set to true, will determine proper encoding and create string which does not break XmlDocument.LoadXml method.

public string GetXmlString(string url)
{
    using var stream = GetResponseStream(url);
    using var reader = new StreamReader(stream, true);
    return reader.ReadToEnd(); // no exception on `LoadXml`
}

Common mistake would be to just blindly use UTF8 encoding on the stream or byte[]. Code bellow would produce string that looks valid when inspected in Visual Studio debugger, or copy-pasted somewhere, but it will produce the exception when used with Load or LoadXml if file is encoded differently then UTF8 without BOM.

public string GetXmlString(string url)
{
    byte[] bytes = GetResponseByteArray(url);
    return System.Text.Encoding.UTF8.GetString(bytes); // potentially exception on `LoadXml`
}

Python dictionary: Get list of values for list of keys

A list comprehension seems to be a good way to do this:

>>> [mydict[x] for x in mykeys]
[3, 1]

CSS Vertical align does not work with float

You need to set line-height.

<div style="border: 1px solid red;">
<span style="font-size: 38px; vertical-align:middle; float:left; line-height: 38px">Hejsan</span>
<span style="font-size: 13px; vertical-align:middle; float:right; line-height: 38px">svejsan</span>
<div style="clear: both;"></div>

http://jsfiddle.net/VBR5J/

Laravel Mail::send() sending to multiple to or bcc addresses

In a scenario where you intend to push a single email to different recipients at one instance (i.e CC multiple email addresses), the solution below works fine with Laravel 5.4 and above.

Mail::to('[email protected]')
    ->cc(['[email protected]','[email protected]','[email protected]','[email protected]'])
    ->send(new document());

where document is any class that further customizes your email.

Get value of c# dynamic property via string

The easiest method for obtaining both a setter and a getter for a property which works for any type including dynamic and ExpandoObject is to use FastMember which also happens to be the fastest method around (it uses Emit).

You can either get a TypeAccessor based on a given type or an ObjectAccessor based of an instance of a given type.

Example:

var staticData = new Test { Id = 1, Name = "France" };
var objAccessor = ObjectAccessor.Create(staticData);
objAccessor["Id"].Should().Be(1);
objAccessor["Name"].Should().Be("France");

var anonymous = new { Id = 2, Name = "Hilton" };
objAccessor = ObjectAccessor.Create(anonymous);
objAccessor["Id"].Should().Be(2);
objAccessor["Name"].Should().Be("Hilton");

dynamic expando = new ExpandoObject();
expando.Id = 3;
expando.Name = "Monica";
objAccessor = ObjectAccessor.Create(expando);
objAccessor["Id"].Should().Be(3);
objAccessor["Name"].Should().Be("Monica");

var typeAccessor = TypeAccessor.Create(staticData.GetType());
typeAccessor[staticData, "Id"].Should().Be(1);
typeAccessor[staticData, "Name"].Should().Be("France");

typeAccessor = TypeAccessor.Create(anonymous.GetType());
typeAccessor[anonymous, "Id"].Should().Be(2);
typeAccessor[anonymous, "Name"].Should().Be("Hilton");

typeAccessor = TypeAccessor.Create(expando.GetType());
((int)typeAccessor[expando, "Id"]).Should().Be(3);
((string)typeAccessor[expando, "Name"]).Should().Be("Monica");

How to add 10 minutes to my (String) time?

I would recommend storing the time as integers and regulate it through the division and modulo operators, once that is done convert the integers into the string format you require.

Skipping every other element after the first

Alternatively, you could do:

for i in range(0, len(a), 2):
    #do something

The extended slice notation is much more concise, though.

How to get the path of current worksheet in VBA?

Use Application.ActiveWorkbook.Path for just the path itself (without the workbook name) or Application.ActiveWorkbook.FullName for the path with the workbook name.

Cannot deserialize instance of object out of START_ARRAY token in Spring Webservice

Taking for granted that the JSON you posted is actually what you are seeing in the browser, then the problem is the JSON itself.

The JSON snippet you have posted is malformed.

You have posted:

[{
        "name" : "shopqwe",
        "mobiles" : [],
        "address" : {
            "town" : "city",
            "street" : "streetqwe",
            "streetNumber" : "59",
            "cordX" : 2.229997,
            "cordY" : 1.002539
        },
        "shoe"[{
                "shoeName" : "addidas",
                "number" : "631744030",
                "producent" : "nike",
                "price" : 999.0,
                "sizes" : [30.0, 35.0, 38.0]
            }]

while the correct JSON would be:

[{
        "name" : "shopqwe",
        "mobiles" : [],
        "address" : {
            "town" : "city",
            "street" : "streetqwe",
            "streetNumber" : "59",
            "cordX" : 2.229997,
            "cordY" : 1.002539
        },
        "shoe" : [{
                "shoeName" : "addidas",
                "number" : "631744030",
                "producent" : "nike",
                "price" : 999.0,
                "sizes" : [30.0, 35.0, 38.0]
            }
        ]
    }
]

What is the most robust way to force a UIView to redraw?

I had a problem with a big delay between calling setNeedsDisplay and drawRect: (5 seconds). It turned out I called setNeedsDisplay in a different thread than the main thread. After moving this call to the main thread the delay went away.

Hope this is of some help.

Getting and removing the first character of a string

removing first characters:

x <- 'hello stackoverflow'
substring(x, 2, nchar(x))

Idea is select all characters starting from 2 to number of characters in x. This is important when you have unequal number of characters in word or phrase.

Selecting the first letter is trivial as previous answers:

substring(x,1,1)

adding 30 minutes to datetime php/mysql

Try this one

DATE_ADD(datefield, INTERVAL 30 MINUTE)

What's the difference between IFrame and Frame?

Inline frame is just one "box" and you can place it anywhere on your site. Frames are a bunch of 'boxes' put together to make one site with many pages.

Javascript swap array elements

Typescript solution that clones the array instead of mutating existing one

export function swapItemsInArray<T>(items: T[], indexA: number, indexB: number): T[] {
  const itemA = items[indexA];

  const clone = [...items];

  clone[indexA] = clone[indexB];
  clone[indexB] = itemA;

  return clone;
}

Why is there an unexplainable gap between these inline-block div elements?

You need to add

#container
{
    display:inline-block;
    position:relative;
    background:rgb(255,100,0);
    margin:0px;
    width:40%;
    height:100px;
    margin-right:-4px;
}

because whenever you write display:inline-block it takes an additional margin-right:4px. So, you need to remove it.

Array of arrays (Python/NumPy)

You'll have problems creating lists without commas. It shouldn't be too hard to transform your data so that it uses commas as separating character.

Once you have commas in there, it's a relatively simple list creation operations:

array1 = [1,2,3]
array2 = [4,5,6]

array3 = [array1, array2]

array4 = [7,8,9]
array5 = [10,11,12]

array3 = [array3, [array4, array5]]

When testing we get:

print(array3)

[[[1, 2, 3], [4, 5, 6]], [[7, 8, 9], [10, 11, 12]]]

And if we test with indexing it works correctly reading the matrix as made up of 2 rows and 2 columns:

array3[0][1]
[4, 5, 6]

array3[1][1]
[10, 11, 12]

Hope that helps.

Capturing Groups From a Grep RegEx

str="1w 2d 1h"
regex="([0-9])w ([0-9])d ([0-9])h"
if [[ $str =~ $regex ]]
then
    week="${BASH_REMATCH[1]}"
    day="${BASH_REMATCH[2]}"
    hour="${BASH_REMATCH[3]}"
    echo $week --- $day ---- $hour
fi

output: 1 --- 2 ---- 1

Google Maps shows "For development purposes only"

As Victoria wrote, Google Maps is no longer free, but you can switch your map provider. You may be interested in OpenStreetMap, there is an easy way to use it on your site described here: https://handyman.dulare.com/switching-from-google-maps-to-openstreetmap/

Unfortunately, on the OpenStreetMap, there is no easy way to provide directions from one point to another, there is also no street view.

error UnicodeDecodeError: 'utf-8' codec can't decode byte 0xff in position 0: invalid start byte

I had a similar issue and searched all the internet for this problem

if you have this problem just copy your HTML code in a new HTML file and use the normal <meta charset="UTF-8"> and it will work....

just create a new HTML file in the same location and use a different name

Easy way to convert a unicode list to a list containing python strings?

Encode each value in the list to a string:

[x.encode('UTF8') for x in EmployeeList]

You need to pick a valid encoding; don't use str() as that'll use the system default (for Python 2 that's ASCII) which will not encode all possible codepoints in a Unicode value.

UTF-8 is capable of encoding all of the Unicode standard, but any codepoint outside the ASCII range will lead to multiple bytes per character.

However, if all you want to do is test for a specific string, test for a unicode string and Python won't have to auto-encode all values when testing for that:

u'1001' in EmployeeList.values()

How can I plot separate Pandas DataFrames as subplots?

You can plot multiple subplots of multiple pandas data frames using matplotlib with a simple trick of making a list of all data frame. Then using the for loop for plotting subplots.

Working code:

import matplotlib.pyplot as plt
import pandas as pd
import numpy as np
# dataframe sample data
df1 = pd.DataFrame(np.random.rand(10,2)*100, columns=['A', 'B'])
df2 = pd.DataFrame(np.random.rand(10,2)*100, columns=['A', 'B'])
df3 = pd.DataFrame(np.random.rand(10,2)*100, columns=['A', 'B'])
df4 = pd.DataFrame(np.random.rand(10,2)*100, columns=['A', 'B'])
df5 = pd.DataFrame(np.random.rand(10,2)*100, columns=['A', 'B'])
df6 = pd.DataFrame(np.random.rand(10,2)*100, columns=['A', 'B'])
#define number of rows and columns for subplots
nrow=3
ncol=2
# make a list of all dataframes 
df_list = [df1 ,df2, df3, df4, df5, df6]
fig, axes = plt.subplots(nrow, ncol)
# plot counter
count=0
for r in range(nrow):
    for c in range(ncol):
        df_list[count].plot(ax=axes[r,c])
        count=+1

enter image description here

Using this code you can plot subplots in any configuration. You need to just define number of rows nrow and number of columns ncol. Also, you need to make list of data frames df_list which you wanted to plot.

UIAlertView first deprecated IOS 9

Make UIAlertController+AlertController Category as:

UIAlertController+AlertController.h

typedef void (^UIAlertCompletionBlock) (UIAlertController *alertViewController, NSInteger buttonIndex);

@interface UIAlertController (AlertController)

+ (instancetype)showAlertIn:(UIViewController *)controller
                  WithTitle:(NSString *)title
                    message:(NSString *)message
          cancelButtonTitle:(NSString *)cancelButtonTitle
          otherButtonTitles:(NSString *)otherButtonTitle
                   tapBlock:(UIAlertCompletionBlock)tapBlock;
@end

UIAlertController+AlertController.m

@implementation UIAlertController (NTAlertController)

+ (instancetype)showAlertIn:(UIViewController *)controller
                  WithTitle:(NSString *)title
                    message:(NSString *)message
          cancelButtonTitle:(NSString *)cancelButtonTitle
          otherButtonTitles:(NSString *)otherButtonTitle
                   tapBlock:(UIAlertCompletionBlock)tapBlock {

    UIAlertController *alertController = [self alertControllerWithTitle:title message:message preferredStyle:UIAlertControllerStyleAlert];

    if(cancelButtonTitle != nil) {

        UIAlertAction *cancelButton = [UIAlertAction
                                       actionWithTitle:cancelButtonTitle
                                       style:UIAlertActionStyleCancel
                                       handler:^(UIAlertAction *action)
                                       {
                                           tapBlock(alertController, ALERTACTION_CANCEL); // CANCEL BUTTON CALL BACK ACTION
                                       }];
        [alertController addAction:cancelButton];

    }

    if(otherButtonTitle != nil) {

        UIAlertAction *otherButton = [UIAlertAction
                                   actionWithTitle:otherButtonTitle
                                   style:UIAlertActionStyleDefault
                                   handler:^(UIAlertAction *action)
                                   {
                                       tapBlock(alertController, ALERTACTION_OTHER); // OTHER BUTTON CALL BACK ACTION
                                   }];

        [alertController addAction:otherButton];
    }

    [controller presentViewController:alertController animated:YES completion:nil];

    return alertController;
}

@end

in your ViewController.m

[UIAlertController showAlertIn:self WithTitle:@"" message:@"" cancelButtonTitle:@"Cancel" otherButtonTitles:@"Other" tapBlock:^(UIAlertController *alertController, NSInteger index){

 if(index == ALERTACTION_CANCEL){

 // CANCEL BUTTON ACTION
 }else
if(index == ALERTACTION_OTHER){

 // OTHER BUTTON ACTION
 }

 [alertController dismissViewControllerAnimated:YES completion:nil];

 }];

NOTE: If you want to add more than two buttons then add another more UIAlertAction to the UIAlertController.

Why does foo = filter(...) return a <filter object>, not a list?

Have a look at the python documentation for filter(function, iterable) (from here):

Construct an iterator from those elements of iterable for which function returns true.

So in order to get a list back you have to use list class:

shesaid = list(filter(greetings(), ["hello", "goodbye"]))

But this probably isn't what you wanted, because it tries to call the result of greetings(), which is "hello", on the values of your input list, and this won't work. Here also the iterator type comes into play, because the results aren't generated until you use them (for example by calling list() on it). So at first you won't get an error, but when you try to do something with shesaid it will stop working:

>>> print(list(shesaid))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: 'str' object is not callable

If you want to check which elements in your list are equal to "hello" you have to use something like this:

shesaid = list(filter(lambda x: x == "hello", ["hello", "goodbye"]))

(I put your function into a lambda, see Randy C's answer for a "normal" function)

Is False == 0 and True == 1 an implementation detail or is it guaranteed by the language?

Link to the PEP discussing the new bool type in Python 2.3: http://www.python.org/dev/peps/pep-0285/.

When converting a bool to an int, the integer value is always 0 or 1, but when converting an int to a bool, the boolean value is True for all integers except 0.

>>> int(False)
0
>>> int(True)
1
>>> bool(5)
True
>>> bool(-5)
True
>>> bool(0)
False

How to count the number of columns in a table using SQL?

select count(*) 
from user_tab_columns
where table_name='MYTABLE' --use upper case

Instead of uppercase you can use lower function. Ex: select count(*) from user_tab_columns where lower(table_name)='table_name';

Exporting to .xlsx using Microsoft.Office.Interop.Excel SaveAs Error

This is how you save the relevant file as a Excel12 (.xlsx) file... It is not as you would intuitively think i.e. using Excel.XlFileFormat.xlExcel12 but Excel.XlFileFormat.xlOpenXMLWorkbook. The actual C# command was

excelWorkbook.SaveAs(strFullFilePathNoExt, Excel.XlFileFormat.xlOpenXMLWorkbook, Missing.Value,
    Missing.Value, false, false, Excel.XlSaveAsAccessMode.xlNoChange, 
    Excel.XlSaveConflictResolution.xlUserResolution, true, 
    Missing.Value, Missing.Value, Missing.Value);

I hope this helps someone else in the future.


Missing.Value is found in the System.Reflection namespace.

Convert Dictionary to JSON in Swift

Swift 4 Dictionary extension.

extension Dictionary {
    var jsonStringRepresentation: String? {
        guard let theJSONData = try? JSONSerialization.data(withJSONObject: self,
                                                            options: [.prettyPrinted]) else {
            return nil
        }

        return String(data: theJSONData, encoding: .ascii)
    }
}

How to force R to use a specified factor level as reference in a regression?

I know this is an old question, but I had a similar issue and found that:

lm(x ~ y + relevel(b, ref = "3")) 

does exactly what you asked.

How to install Guest addition in Mac OS as guest and Windows machine as host

  1. In the guest Mac, open the Terminal and go for a reboot on the Recovery partition
sudo nvram "recovery-boot-mode=unused"
sudo reboot
  1. Now you're in Recovery mode, enter the Terminal and do:
csrutil disable
spctl kext-consent add VB5E2TV963
nvram -d recovery-boot-mode
reboot
  1. Back in "normal" mode, open the Terminal, and do:
sudo mount -uw /
sudo chown :admin /System/Library/Extensions/
sudo chmod 775 /System/Library/Extensions/
  1. Run the Guest Additions installer and go through the end (in principle, it goes through successfully)

  2. Now in the terminal, do:

sudo chown :wheel /System/Library/Extensions/
sudo chmod 755 /System/Library/Extensions/
sudo nvram "recovery-boot-mode=unused"
sudo reboot
  1. Again in Recovery mode, go into the Terminal and do:
csrutil enable
nvram -d recovery-boot-mode
reboot

You should be set.

Laravel Request getting current path with query string

public functin func_name(Request $request){$reqOutput = $request->getRequestUri();}

jQuery autoComplete view all on click?

When input value is empty search else the value inside input. This code works for me:

$("#your_input").on('focus', function () {
   $(this).autocomplete('search', $(this).val() == '' ? " " : $(this).val());    
});

Concatenating date with a string in Excel

This is the numerical representation of the date. The thing you get when referring to dates from formulas like that.

You'll have to do:

= A1 & TEXT(A2, "mm/dd/yyyy")

The biggest problem here is that the format specifier is locale-dependent. It will not work/produce not what expected if the file is opened with a differently localized Excel.

Now, you could have a user-defined function:

public function AsDisplayed(byval c as range) as string
  AsDisplayed = c.Text
end function

and then

= A1 & AsDisplayed(A2)

But then there's a bug (feature?) in Excel because of which the .Text property is suddenly not available during certain stages of the computation cycle, and your formulas display #VALUE instead of what they should.

That is, it's bad either way.

Setting transparent images background in IrfanView

You were on the right track. IrfanView sets the background for transparency the same as the viewing color around the image.

You just need to re-open the image with IrfanView after changing the view color to white.

To change the viewing color in Irfanview go to:

Options > Properties/Settings > Viewing > Main window color

Why SpringMVC Request method 'GET' not supported?

method = POST will work if you 'post' a form to the url /test.

if you type a url in address bar of a browser and hit enter, it's always a GET request, so you had to specify POST request.

Google for HTTP GET and HTTP POST (there are several others like PUT DELETE). They all have their own meaning.

How do I export an Android Studio project?

Apparently, there's a lot of "dead wood" in the "build" directories of a project.

Under linux/unix, a simple way to get a clean, private backup is to use the "tar" command along with the "--exclude=String" option.

For example, to create an archive of all my apps while excluding the build directories, I have a script that creates the following 2 commands :

cd $HOME/android/Studio
tar cvf MyBackup-2017-07-13.tar Projects --exclude=build

python how to pad numpy array with zeros

NumPy 1.7.0 (when numpy.pad was added) is pretty old now (it was released in 2013) so even though the question asked for a way without using that function I thought it could be useful to know how that could be achieved using numpy.pad.

It's actually pretty simple:

>>> import numpy as np
>>> a = np.array([[ 1.,  1.,  1.,  1.,  1.],
...               [ 1.,  1.,  1.,  1.,  1.],
...               [ 1.,  1.,  1.,  1.,  1.]])
>>> np.pad(a, [(0, 1), (0, 1)], mode='constant')
array([[ 1.,  1.,  1.,  1.,  1.,  0.],
       [ 1.,  1.,  1.,  1.,  1.,  0.],
       [ 1.,  1.,  1.,  1.,  1.,  0.],
       [ 0.,  0.,  0.,  0.,  0.,  0.]])

In this case I used that 0 is the default value for mode='constant'. But it could also be specified by passing it in explicitly:

>>> np.pad(a, [(0, 1), (0, 1)], mode='constant', constant_values=0)
array([[ 1.,  1.,  1.,  1.,  1.,  0.],
       [ 1.,  1.,  1.,  1.,  1.,  0.],
       [ 1.,  1.,  1.,  1.,  1.,  0.],
       [ 0.,  0.,  0.,  0.,  0.,  0.]])

Just in case the second argument ([(0, 1), (0, 1)]) seems confusing: Each list item (in this case tuple) corresponds to a dimension and item therein represents the padding before (first element) and after (second element). So:

[(0, 1), (0, 1)]
         ^^^^^^------ padding for second dimension
 ^^^^^^-------------- padding for first dimension

  ^------------------ no padding at the beginning of the first axis
     ^--------------- pad with one "value" at the end of the first axis.

In this case the padding for the first and second axis are identical, so one could also just pass in the 2-tuple:

>>> np.pad(a, (0, 1), mode='constant')
array([[ 1.,  1.,  1.,  1.,  1.,  0.],
       [ 1.,  1.,  1.,  1.,  1.,  0.],
       [ 1.,  1.,  1.,  1.,  1.,  0.],
       [ 0.,  0.,  0.,  0.,  0.,  0.]])

In case the padding before and after is identical one could even omit the tuple (not applicable in this case though):

>>> np.pad(a, 1, mode='constant')
array([[ 0.,  0.,  0.,  0.,  0.,  0.,  0.],
       [ 0.,  1.,  1.,  1.,  1.,  1.,  0.],
       [ 0.,  1.,  1.,  1.,  1.,  1.,  0.],
       [ 0.,  1.,  1.,  1.,  1.,  1.,  0.],
       [ 0.,  0.,  0.,  0.,  0.,  0.,  0.]])

Or if the padding before and after is identical but different for the axis, you could also omit the second argument in the inner tuples:

>>> np.pad(a, [(1, ), (2, )], mode='constant')
array([[ 0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.],
       [ 0.,  0.,  1.,  1.,  1.,  1.,  1.,  0.,  0.],
       [ 0.,  0.,  1.,  1.,  1.,  1.,  1.,  0.,  0.],
       [ 0.,  0.,  1.,  1.,  1.,  1.,  1.,  0.,  0.],
       [ 0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.]])

However I tend to prefer to always use the explicit one, because it's just to easy to make mistakes (when NumPys expectations differ from your intentions):

>>> np.pad(a, [1, 2], mode='constant')
array([[ 0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.],
       [ 0.,  1.,  1.,  1.,  1.,  1.,  0.,  0.],
       [ 0.,  1.,  1.,  1.,  1.,  1.,  0.,  0.],
       [ 0.,  1.,  1.,  1.,  1.,  1.,  0.,  0.],
       [ 0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.],
       [ 0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.]])

Here NumPy thinks you wanted to pad all axis with 1 element before and 2 elements after each axis! Even if you intended it to pad with 1 element in axis 1 and 2 elements for axis 2.

I used lists of tuples for the padding, note that this is just "my convention", you could also use lists of lists or tuples of tuples, or even tuples of arrays. NumPy just checks the length of the argument (or if it doesn't have a length) and the length of each item (or if it has a length)!

How to determine the version of the C++ standard used by the compiler?

__cplusplus

In C++0x the macro __cplusplus will be set to a value that differs from (is greater than) the current 199711L.

C++0x FAQ by BS

Angular2 http.get() ,map(), subscribe() and observable pattern - basic understanding

import { HttpClientModule } from '@angular/common/http';

The HttpClient API was introduced in the version 4.3.0. It is an evolution of the existing HTTP API and has it's own package @angular/common/http. One of the most notable changes is that now the response object is a JSON by default, so there's no need to parse it with map method anymore .Straight away we can use like below

http.get('friends.json').subscribe(result => this.result =result);

How to Find the Default Charset/Encoding in Java?

I have set the vm argument in WAS server as -Dfile.encoding=UTF-8 to change the servers' default character set.

Changing :hover to touch/click for mobile devices

You can add onclick="" to hovered element. Hover will work after that.

Edit: But you really shouldn't add anything style related to your markup, just posted it as an alternative.

Store List to session

Yes. Which platform are you writing for? ASP.NET C#?

List<string> myList = new List<string>();
Session["var"] = myList;

Then, to retrieve:

myList = (List<string>)Session["var"];

Plotting a 3d cube, a sphere and a vector in Matplotlib

My answer is an amalgamation of the above two with extension to drawing sphere of user-defined opacity and some annotation. It finds application in b-vector visualization on a sphere for magnetic resonance image (MRI). Hope you find it useful:

from mpl_toolkits.mplot3d import Axes3D
import matplotlib.pyplot as plt
import numpy as np

fig = plt.figure()
ax = fig.gca(projection='3d')

# draw sphere
u, v = np.mgrid[0:2*np.pi:50j, 0:np.pi:50j]
x = np.cos(u)*np.sin(v)
y = np.sin(u)*np.sin(v)
z = np.cos(v)
# alpha controls opacity
ax.plot_surface(x, y, z, color="g", alpha=0.3)


# a random array of 3D coordinates in [-1,1]
bvecs= np.random.randn(20,3)

# tails of the arrows
tails= np.zeros(len(bvecs))

# heads of the arrows with adjusted arrow head length
ax.quiver(tails,tails,tails,bvecs[:,0], bvecs[:,1], bvecs[:,2],
          length=1.0, normalize=True, color='r', arrow_length_ratio=0.15)

ax.set_xlabel('X-axis')
ax.set_ylabel('Y-axis')
ax.set_zlabel('Z-axis')

ax.set_title('b-vectors on unit sphere')

plt.show()

How can I concatenate strings in VBA?

The main (very interesting) difference for me is that:
"string" & Null -> "string"
while
"string" + Null -> Null

But that's probably more useful in database apps like Access.

How to generate an openSSL key using a passphrase from the command line?

If you don't use a passphrase, then the private key is not encrypted with any symmetric cipher - it is output completely unprotected.

You can generate a keypair, supplying the password on the command-line using an invocation like (in this case, the password is foobar):

openssl genrsa -aes128 -passout pass:foobar 3072

However, note that this passphrase could be grabbed by any other process running on the machine at the time, since command-line arguments are generally visible to all processes.

A better alternative is to write the passphrase into a temporary file that is protected with file permissions, and specify that:

openssl genrsa -aes128 -passout file:passphrase.txt 3072

Or supply the passphrase on standard input:

openssl genrsa -aes128 -passout stdin 3072

You can also used a named pipe with the file: option, or a file descriptor.


To then obtain the matching public key, you need to use openssl rsa, supplying the same passphrase with the -passin parameter as was used to encrypt the private key:

openssl rsa -passin file:passphrase.txt -pubout

(This expects the encrypted private key on standard input - you can instead read it from a file using -in <file>).


Example of creating a 3072-bit private and public key pair in files, with the private key pair encrypted with password foobar:

openssl genrsa -aes128 -passout pass:foobar -out privkey.pem 3072
openssl rsa -in privkey.pem -passin pass:foobar -pubout -out privkey.pub

macro for Hide rows in excel 2010

You almost got it. You are hiding the rows within the active sheet. which is okay. But a better way would be add where it is.

Rows("52:55").EntireRow.Hidden = False

becomes

activesheet.Rows("52:55").EntireRow.Hidden = False

i've had weird things happen without it. As for making it automatic. You need to use the worksheet_change event within the sheet's macro in the VBA editor (not modules, double click the sheet1 to the far left of the editor.) Within that sheet, use the drop down menu just above the editor itself (there should be 2 listboxes). The listbox to the left will have the events you are looking for. After that just throw in the macro. It should look like the below code,

Private Sub Worksheet_Change(ByVal Target As Range)
test1
end Sub

That's it. Anytime you change something, it will run the macro test1.

How do I set multipart in axios with react?

If you are sending alphanumeric data try changing

'Content-Type': 'multipart/form-data'

to

'Content-Type': 'application/x-www-form-urlencoded'

If you are sending non-alphanumeric data try to remove 'Content-Type' at all.

If it still does not work, consider trying request-promise (at least to test whether it is really axios problem or not)

get original element from ng-click

Not a direct answer to this question but rather to the "issue" of $event.currentTarget apparently be set to null.

This is due to the fact that console.log shows deep mutable objects at the last state of execution, not at the state when console.log was called.

You can check this for more information: Consecutive calls to console.log produce inconsistent results

HTML - How to do a Confirmation popup to a Submit button and then send the request?

I believe you want to use confirm()

<script type="text/javascript">
    function clicked() {
       if (confirm('Do you want to submit?')) {
           yourformelement.submit();
       } else {
           return false;
       }
    }

</script>

How to clear Tkinter Canvas?

Every canvas item is an object that Tkinter keeps track of. If you are clearing the screen by just drawing a black rectangle, then you effectively have created a memory leak -- eventually your program will crash due to the millions of items that have been drawn.

To clear a canvas, use the delete method. Give it the special parameter "all" to delete all items on the canvas (the string "all"" is a special tag that represents all items on the canvas):

canvas.delete("all")

If you want to delete only certain items on the canvas (such as foreground objects, while leaving the background objects on the display) you can assign tags to each item. Then, instead of "all", you could supply the name of a tag.

If you're creating a game, you probably don't need to delete and recreate items. For example, if you have an object that is moving across the screen, you can use the move or coords method to move the item.

You have not concluded your merge (MERGE_HEAD exists)

Blockquote

If you're trying to pull from another branch into your branch. If you're seeing this error.

First, you should try doing git commit and then pull another branch into yours.

  1. "git add . "
  2. git commit
  3. Then do git pull from the required branch.

Functions are not valid as a React child. This may happen if you return a Component instead of from render

In my case i forgot to add the () after the function name inside the render function of a react component

public render() {
       let ctrl = (
           <>
                <div className="aaa">
                    {this.renderView}
                </div>
            </>
       ); 

       return ctrl;
    };


    private renderView() : JSX.Element {
        // some html
    };

Changing the render method, as it states in the error message to

        <div className="aaa">
            {this.renderView()}
        </div>

fixed the problem

Remove all special characters from a string

This should do what you're looking for:

function clean($string) {
   $string = str_replace(' ', '-', $string); // Replaces all spaces with hyphens.

   return preg_replace('/[^A-Za-z0-9\-]/', '', $string); // Removes special chars.
}

Usage:

echo clean('a|"bc!@£de^&$f g');

Will output: abcdef-g

Edit:

Hey, just a quick question, how can I prevent multiple hyphens from being next to each other? and have them replaced with just 1?

function clean($string) {
   $string = str_replace(' ', '-', $string); // Replaces all spaces with hyphens.
   $string = preg_replace('/[^A-Za-z0-9\-]/', '', $string); // Removes special chars.

   return preg_replace('/-+/', '-', $string); // Replaces multiple hyphens with single one.
}

What are passive event listeners?

Passive event listeners are an emerging web standard, new feature shipped in Chrome 51 that provide a major potential boost to scroll performance. Chrome Release Notes.

It enables developers to opt-in to better scroll performance by eliminating the need for scrolling to block on touch and wheel event listeners.

Problem: All modern browsers have a threaded scrolling feature to permit scrolling to run smoothly even when expensive JavaScript is running, but this optimization is partially defeated by the need to wait for the results of any touchstart and touchmove handlers, which may prevent the scroll entirely by calling preventDefault() on the event.

Solution: {passive: true}

By marking a touch or wheel listener as passive, the developer is promising the handler won't call preventDefault to disable scrolling. This frees the browser up to respond to scrolling immediately without waiting for JavaScript, thus ensuring a reliably smooth scrolling experience for the user.

document.addEventListener("touchstart", function(e) {
    console.log(e.defaultPrevented);  // will be false
    e.preventDefault();   // does nothing since the listener is passive
    console.log(e.defaultPrevented);  // still false
}, Modernizr.passiveeventlisteners ? {passive: true} : false);

DOM Spec , Demo Video , Explainer Doc

Add missing dates to pandas dataframe

You could use Series.reindex:

import pandas as pd

idx = pd.date_range('09-01-2013', '09-30-2013')

s = pd.Series({'09-02-2013': 2,
               '09-03-2013': 10,
               '09-06-2013': 5,
               '09-07-2013': 1})
s.index = pd.DatetimeIndex(s.index)

s = s.reindex(idx, fill_value=0)
print(s)

yields

2013-09-01     0
2013-09-02     2
2013-09-03    10
2013-09-04     0
2013-09-05     0
2013-09-06     5
2013-09-07     1
2013-09-08     0
...

Is it possible to set a timeout for an SQL query on Microsoft SQL server?

You can specify the connection timeout within the SQL connection string, when you connect to the database, like so:

"Data Source=localhost;Initial Catalog=database;Connect Timeout=15"

On the server level, use MSSQLMS to view the server properties, and on the Connections page you can specify the default query timeout.

I'm not quite sure that queries keep on running after the client connection has closed. Queries should not take that long either, MSSQL can handle large databases, I've worked with GB's of data on it before. Run a performance profile on the queries, prehaps some well-placed indexes could speed it up, or rewriting the query could too.

Update: According to this list, SQL timeouts happen when waiting for attention acknowledgement from server:

Suppose you execute a command, then the command times out. When this happens the SqlClient driver sends a special 8 byte packet to the server called an attention packet. This tells the server to stop executing the current command. When we send the attention packet, we have to wait for the attention acknowledgement from the server and this can in theory take a long time and time out. You can also send this packet by calling SqlCommand.Cancel on an asynchronous SqlCommand object. This one is a special case where we use a 5 second timeout. In most cases you will never hit this one, the server is usually very responsive to attention packets because these are handled very low in the network layer.

So it seems that after the client connection times out, a signal is sent to the server to cancel the running query too.

What is the purpose of the "role" attribute in HTML?

I realise this is an old question, but another possible consideration depending on your exact requirements is that validating on https://validator.w3.org/ generates warnings as follows:

Warning: The form role is unnecessary for element form.

how to convert image to byte array in java?

Using RandomAccessFile would be simple and handy.

RandomAccessFile f = new RandomAccessFile(filepath, "r");
byte[] bytes = new byte[(int) f.length()];
f.read(bytes);
f.close();

Filter values only if not null using lambda in Java8

In this particular example I think @Tagir is 100% correct get it into one filter and do the two checks. I wouldn't use Optional.ofNullable the Optional stuff is really for return types not to be doing logic... but really neither here nor there.

I wanted to point out that java.util.Objects has a nice method for this in a broad case, so you can do this:

cars.stream()
    .filter(Objects::nonNull)

Which will clear out your null objects. For anyone not familiar, that's the short-hand for the following:

cars.stream()
    .filter(car -> Objects.nonNull(car))

To partially answer the question at hand to return the list of car names that starts with "M":

cars.stream()
    .filter(car -> Objects.nonNull(car))
    .map(car -> car.getName())
    .filter(carName -> Objects.nonNull(carName))
    .filter(carName -> carName.startsWith("M"))
    .collect(Collectors.toList());

Once you get used to the shorthand lambdas you could also do this:

cars.stream()
    .filter(Objects::nonNull)
    .map(Car::getName)        // Assume the class name for car is Car
    .filter(Objects::nonNull)
    .filter(carName -> carName.startsWith("M"))
    .collect(Collectors.toList());

Unfortunately once you .map(Car::getName) you'll only be returning the list of names, not the cars. So less beautiful but fully answers the question:

cars.stream()
    .filter(car -> Objects.nonNull(car))
    .filter(car -> Objects.nonNull(car.getName()))
    .filter(car -> car.getName().startsWith("M"))
    .collect(Collectors.toList());

How can I get a list of all classes within current module in Python?

I don't know if there's a 'proper' way to do it, but your snippet is on the right track: just add import foo to foo.py, do inspect.getmembers(foo), and it should work fine.

Get absolute path to workspace directory in Jenkins Pipeline plugin

Since version 2.5 of the Pipeline Nodes and Processes Plugin (a component of the Pipeline plugin, installed by default), the WORKSPACE environment variable is available again. This version was released on 2016-09-23, so it should be available on all up-to-date Jenkins instances.

Example

node('label'){
    // now you are on slave labeled with 'label'
    def workspace = WORKSPACE
    // ${workspace} will now contain an absolute path to job workspace on slave

    workspace = env.WORKSPACE
    // ${workspace} will still contain an absolute path to job workspace on slave

    // When using a GString at least later Jenkins versions could only handle the env.WORKSPACE variant:
    echo "Current workspace is ${env.WORKSPACE}"

    // the current Jenkins instances will support the short syntax, too:
    echo "Current workspace is $WORKSPACE"

}

Use virtualenv with Python with Visual Studio Code in Ubuntu

It seems to be (as of 2018.03) in code-insider. A directive has been introduced called python.venvFolders:

  "python.venvFolders": [
    "envs",
    ".pyenv",
    ".direnv"
  ],

All you need is to add your virtualenv folder name.

What's the proper way to "go get" a private repository?

After setting up GOPRIVATE and git config ...

People may still meeting problems like this when fetching private source:

https fetch: Get "https://private/user/repo?go-get=1": EOF

They can't use private repo without .git extension.

The reason is the go tool has no idea about the VCS protocol of this repo, git or svn or any other, unlike github.com or golang.org them are hardcoded into go's source.

Then the go tool will do a https query before fetching your private repo:

https://private/user/repo?go-get=1

If your private repo has no support for https request, please use replace to tell it directly :

require private/user/repo v1.0.0

...

replace private/user/repo => private.server/user/repo.git v1.0.0

https://golang.org/cmd/go/#hdr-Remote_import_paths

Why shouldn't I use mysql_* functions in PHP?

This answer is written to show just how trivial it is to bypass poorly written PHP user-validation code, how (and using what) these attacks work and how to replace the old MySQL functions with a secure prepared statement - and basically, why StackOverflow users (probably with a lot of rep) are barking at new users asking questions to improve their code.

First off, please feel free to create this test mysql database (I have called mine prep):

mysql> create table users(
    -> id int(2) primary key auto_increment,
    -> userid tinytext,
    -> pass tinytext);
Query OK, 0 rows affected (0.05 sec)

mysql> insert into users values(null, 'Fluffeh', 'mypass');
Query OK, 1 row affected (0.04 sec)

mysql> create user 'prepared'@'localhost' identified by 'example';
Query OK, 0 rows affected (0.01 sec)

mysql> grant all privileges on prep.* to 'prepared'@'localhost' with grant option;
Query OK, 0 rows affected (0.00 sec)

With that done, we can move to our PHP code.

Lets assume the following script is the verification process for an admin on a website (simplified but working if you copy and use it for testing):

<?php 

    if(!empty($_POST['user']))
    {
        $user=$_POST['user'];
    }   
    else
    {
        $user='bob';
    }
    if(!empty($_POST['pass']))
    {
        $pass=$_POST['pass'];
    }
    else
    {
        $pass='bob';
    }

    $database='prep';
    $link=mysql_connect('localhost', 'prepared', 'example');
    mysql_select_db($database) or die( "Unable to select database");

    $sql="select id, userid, pass from users where userid='$user' and pass='$pass'";
    //echo $sql."<br><br>";
    $result=mysql_query($sql);
    $isAdmin=false;
    while ($row = mysql_fetch_assoc($result)) {
        echo "My id is ".$row['id']." and my username is ".$row['userid']." and lastly, my password is ".$row['pass']."<br>";
        $isAdmin=true;
        // We have correctly matched the Username and Password
        // Lets give this person full access
    }
    if($isAdmin)
    {
        echo "The check passed. We have a verified admin!<br>";
    }
    else
    {
        echo "You could not be verified. Please try again...<br>";
    }
    mysql_close($link);

?>

<form name="exploited" method='post'>
    User: <input type='text' name='user'><br>
    Pass: <input type='text' name='pass'><br>
    <input type='submit'>
</form>

Seems legit enough at first glance.

The user has to enter a login and password, right?

Brilliant, not enter in the following:

user: bob
pass: somePass

and submit it.

The output is as follows:

You could not be verified. Please try again...

Super! Working as expected, now lets try the actual username and password:

user: Fluffeh
pass: mypass

Amazing! Hi-fives all round, the code correctly verified an admin. It's perfect!

Well, not really. Lets say the user is a clever little person. Lets say the person is me.

Enter in the following:

user: bob
pass: n' or 1=1 or 'm=m

And the output is:

The check passed. We have a verified admin!

Congrats, you just allowed me to enter your super-protected admins only section with me entering a false username and a false password. Seriously, if you don't believe me, create the database with the code I provided, and run this PHP code - which at glance REALLY does seem to verify the username and password rather nicely.

So, in answer, THAT IS WHY YOU ARE BEING YELLED AT.

So, lets have a look at what went wrong, and why I just got into your super-admin-only-bat-cave. I took a guess and assumed that you weren't being careful with your inputs and simply passed them to the database directly. I constructed the input in a way tht would CHANGE the query that you were actually running. So, what was it supposed to be, and what did it end up being?

select id, userid, pass from users where userid='$user' and pass='$pass'

That's the query, but when we replace the variables with the actual inputs that we used, we get the following:

select id, userid, pass from users where userid='bob' and pass='n' or 1=1 or 'm=m'

See how I constructed my "password" so that it would first close the single quote around the password, then introduce a completely new comparison? Then just for safety, I added another "string" so that the single quote would get closed as expected in the code we originally had.

However, this isn't about folks yelling at you now, this is about showing you how to make your code more secure.

Okay, so what went wrong, and how can we fix it?

This is a classic SQL injection attack. One of the simplest for that matter. On the scale of attack vectors, this is a toddler attacking a tank - and winning.

So, how do we protect your sacred admin section and make it nice and secure? The first thing to do will be to stop using those really old and deprecated mysql_* functions. I know, you followed a tutorial you found online and it works, but it's old, it's outdated and in the space of a few minutes, I have just broken past it without so much as breaking a sweat.

Now, you have the better options of using mysqli_ or PDO. I am personally a big fan of PDO, so I will be using PDO in the rest of this answer. There are pro's and con's, but personally I find that the pro's far outweigh the con's. It's portable across multiple database engines - whether you are using MySQL or Oracle or just about bloody anything - just by changing the connection string, it has all the fancy features we want to use and it is nice and clean. I like clean.

Now, lets have a look at that code again, this time written using a PDO object:

<?php 

    if(!empty($_POST['user']))
    {
        $user=$_POST['user'];
    }   
    else
    {
        $user='bob';
    }
    if(!empty($_POST['pass']))
    {
        $pass=$_POST['pass'];
    }
    else
    {
        $pass='bob';
    }
    $isAdmin=false;

    $database='prep';
    $pdo=new PDO ('mysql:host=localhost;dbname=prep', 'prepared', 'example');
    $sql="select id, userid, pass from users where userid=:user and pass=:password";
    $myPDO = $pdo->prepare($sql, array(PDO::ATTR_CURSOR => PDO::CURSOR_FWDONLY));
    if($myPDO->execute(array(':user' => $user, ':password' => $pass)))
    {
        while($row=$myPDO->fetch(PDO::FETCH_ASSOC))
        {
            echo "My id is ".$row['id']." and my username is ".$row['userid']." and lastly, my password is ".$row['pass']."<br>";
            $isAdmin=true;
            // We have correctly matched the Username and Password
            // Lets give this person full access
        }
    }

    if($isAdmin)
    {
        echo "The check passed. We have a verified admin!<br>";
    }
    else
    {
        echo "You could not be verified. Please try again...<br>";
    }

?>

<form name="exploited" method='post'>
    User: <input type='text' name='user'><br>
    Pass: <input type='text' name='pass'><br>
    <input type='submit'>
</form>

The major differences are that there are no more mysql_* functions. It's all done via a PDO object, secondly, it is using a prepared statement. Now, what's a prepred statement you ask? It's a way to tell the database ahead of running a query, what the query is that we are going to run. In this case, we tell the database: "Hi, I am going to run a select statement wanting id, userid and pass from the table users where the userid is a variable and the pass is also a variable.".

Then, in the execute statement, we pass the database an array with all the variables that it now expects.

The results are fantastic. Lets try those username and password combinations from before again:

user: bob
pass: somePass

User wasn't verified. Awesome.

How about:

user: Fluffeh
pass: mypass

Oh, I just got a little excited, it worked: The check passed. We have a verified admin!

Now, lets try the data that a clever chap would enter to try to get past our little verification system:

user: bob
pass: n' or 1=1 or 'm=m

This time, we get the following:

You could not be verified. Please try again...

This is why you are being yelled at when posting questions - it's because people can see that your code can be bypassed wihout even trying. Please, do use this question and answer to improve your code, to make it more secure and to use functions that are current.

Lastly, this isn't to say that this is PERFECT code. There are many more things that you could do to improve it, use hashed passwords for example, ensure that when you store sensetive information in the database, you don't store it in plain text, have multiple levels of verification - but really, if you just change your old injection prone code to this, you will be WELL along the way to writing good code - and the fact that you have gotten this far and are still reading gives me a sense of hope that you will not only implement this type of code when writing your websites and applications, but that you might go out and research those other things I just mentioned - and more. Write the best code you can, not the most basic code that barely functions.

How to convert DataSet to DataTable

Here is my solution:

DataTable datatable = (DataTable)dataset.datatablename;

Java - How to create a custom dialog box?

Try this simple class for customizing a dialog to your liking:

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

import javax.swing.JComponent;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JRootPane;

public class CustomDialog
{
    private List<JComponent> components;

    private String title;
    private int messageType;
    private JRootPane rootPane;
    private String[] options;
    private int optionIndex;

    public CustomDialog()
    {
        components = new ArrayList<>();

        setTitle("Custom dialog");
        setMessageType(JOptionPane.PLAIN_MESSAGE);
        setRootPane(null);
        setOptions(new String[] { "OK", "Cancel" });
        setOptionSelection(0);
    }

    public void setTitle(String title)
    {
        this.title = title;
    }

    public void setMessageType(int messageType)
    {
        this.messageType = messageType;
    }

    public void addComponent(JComponent component)
    {
        components.add(component);
    }

    public void addMessageText(String messageText)
    {
        JLabel label = new JLabel("<html>" + messageText + "</html>");

        components.add(label);
    }

    public void setRootPane(JRootPane rootPane)
    {
        this.rootPane = rootPane;
    }

    public void setOptions(String[] options)
    {
        this.options = options;
    }

    public void setOptionSelection(int optionIndex)
    {
        this.optionIndex = optionIndex;
    }

    public int show()
    {
        int optionType = JOptionPane.OK_CANCEL_OPTION;
        Object optionSelection = null;

        if(options.length != 0)
        {
            optionSelection = options[optionIndex];
        }

        int selection = JOptionPane.showOptionDialog(rootPane,
                components.toArray(), title, optionType, messageType, null,
                options, optionSelection);

        return selection;
    }

    public static String getLineBreak()
    {
        return "<br>";
    }
}

Copy all files with a certain extension from all subdirectories

--parents is copying the directory structure, so you should get rid of that.

The way you've written this, the find executes, and the output is put onto the command line such that cp can't distinguish between the spaces separating the filenames, and the spaces within the filename. It's better to do something like

$ find . -name \*.xls -exec cp {} newDir \;

in which cp is executed for each filename that find finds, and passed the filename correctly. Here's more info on this technique.

Instead of all the above, you could use zsh and simply type

$ cp **/*.xls target_directory

zsh can expand wildcards to include subdirectories and makes this sort of thing very easy.

Regex allow a string to only contain numbers 0 - 9 and limit length to 45

A combination of both attempts is probably what you need:

^[0-9]{1,45}$

How to access your website through LAN in ASP.NET

You will need to configure you IIS (assuming this is the web server your are/will using) allowing access from WLAN/LAN to specific users (or anonymous). Allow IIS trought your firewall if you have one.

Your application won't need to be changed, that's just networking problems ans configuration you will have to face to allow acces only trought LAN and WLAN.

Quick way to create a list of values in C#?

In C# 3, you can do:

IList<string> l = new List<string> { "test1", "test2", "test3" };

This uses the new collection initializer syntax in C# 3.

In C# 2, I would just use your second option.

segmentation fault : 11

Your array is occupying roughly 8 GB of memory (1,000 x 1,000,000 x sizeof(double) bytes). That might be a factor in your problem. It is a global variable rather than a stack variable, so you may be OK, but you're pushing limits here.

Writing that much data to a file is going to take a while.

You don't check that the file was opened successfully, which could be a source of trouble, too (if it did fail, a segmentation fault is very likely).

You really should introduce some named constants for 1,000 and 1,000,000; what do they represent?

You should also write a function to do the calculation; you could use an inline function in C99 or later (or C++). The repetition in the code is excruciating to behold.

You should also use C99 notation for main(), with the explicit return type (and preferably void for the argument list when you are not using argc or argv):

int main(void)

Out of idle curiosity, I took a copy of your code, changed all occurrences of 1000 to ROWS, all occurrences of 1000000 to COLS, and then created enum { ROWS = 1000, COLS = 10000 }; (thereby reducing the problem size by a factor of 100). I made a few minor changes so it would compile cleanly under my preferred set of compilation options (nothing serious: static in front of the functions, and the main array; file becomes a local to main; error check the fopen(), etc.).

I then created a second copy and created an inline function to do the repeated calculation, (and a second one to do subscript calculations). This means that the monstrous expression is only written out once — which is highly desirable as it ensure consistency.

#include <stdio.h>

#define   lambda   2.0
#define   g        1.0
#define   F0       1.0
#define   h        0.1
#define   e        0.00001

enum { ROWS = 1000, COLS = 10000 };

static double F[ROWS][COLS];

static void Inicio(double D[ROWS][COLS])
{
    for (int i = 399; i < 600; i++) // Magic numbers!!
        D[i][0] = F0;
}

enum { R = ROWS - 1 };

static inline int ko(int k, int n)
{
    int rv = k + n;
    if (rv >= R)
        rv -= R;
    else if (rv < 0)
        rv += R;
    return(rv);
}

static inline void calculate_value(int i, int k, double A[ROWS][COLS])
{
    int ks2 = ko(k, -2);
    int ks1 = ko(k, -1);
    int kp1 = ko(k, +1);
    int kp2 = ko(k, +2);

    A[k][i] = A[k][i-1]
            + e/(h*h*h*h) * g*g * (A[kp2][i-1] - 4.0*A[kp1][i-1] + 6.0*A[k][i-1] - 4.0*A[ks1][i-1] + A[ks2][i-1])
            + 2.0*g*e/(h*h) * (A[kp1][i-1] - 2*A[k][i-1] + A[ks1][i-1])
            + e * A[k][i-1] * (lambda - A[k][i-1] * A[k][i-1]);
}

static void Iteration(double A[ROWS][COLS])
{
    for (int i = 1; i < COLS; i++)
    {
        for (int k = 0; k < R; k++)
            calculate_value(i, k, A);
        A[999][i] = A[0][i];
    }
}

int main(void)
{
    FILE *file = fopen("P2.txt","wt");
    if (file == 0)
        return(1);
    Inicio(F);
    Iteration(F);
    for (int i = 0; i < COLS; i++)
    {
        for (int j = 0; j < ROWS; j++)
        {
            fprintf(file,"%lf \t %.4f \t %lf\n", 1.0*j/10.0, 1.0*i, F[j][i]);
        }
    }
    fclose(file);
    return(0);
}

This program writes to P2.txt instead of P1.txt. I ran both programs and compared the output files; the output was identical. When I ran the programs on a mostly idle machine (MacBook Pro, 2.3 GHz Intel Core i7, 16 GiB 1333 MHz RAM, Mac OS X 10.7.5, GCC 4.7.1), I got reasonably but not wholly consistent timing:

Original   Modified
6.334s      6.367s
6.241s      6.231s
6.315s     10.778s
6.378s      6.320s
6.388s      6.293s
6.285s      6.268s
6.387s     10.954s
6.377s      6.227s
8.888s      6.347s
6.304s      6.286s
6.258s     10.302s
6.975s      6.260s
6.663s      6.847s
6.359s      6.313s
6.344s      6.335s
7.762s      6.533s
6.310s      9.418s
8.972s      6.370s
6.383s      6.357s

However, almost all that time is spent on disk I/O. I reduced the disk I/O to just the very last row of data, so the outer I/O for loop became:

for (int i = COLS - 1; i < COLS; i++)

the timings were vastly reduced and very much more consistent:

Original    Modified
0.168s      0.165s
0.145s      0.165s
0.165s      0.166s
0.164s      0.163s
0.151s      0.151s
0.148s      0.153s
0.152s      0.171s
0.165s      0.165s
0.173s      0.176s
0.171s      0.165s
0.151s      0.169s

The simplification in the code from having the ghastly expression written out just once is very beneficial, it seems to me. I'd certainly far rather have to maintain that program than the original.

generate model using user:references vs user_id:integer

Both will generate the same columns when you run the migration. In rails console, you can see that this is the case:

:001 > Micropost
=> Micropost(id: integer, user_id: integer, created_at: datetime, updated_at: datetime)

The second command adds a belongs_to :user relationship in your Micropost model whereas the first does not. When this relationship is specified, ActiveRecord will assume that the foreign key is kept in the user_id column and it will use a model named User to instantiate the specific user.

The second command also adds an index on the new user_id column.

gitx How do I get my 'Detached HEAD' commits back into master

If checkout master was the last thing you did, then the reflog entry HEAD@{1} will contain your commits (otherwise use git reflog or git log -p to find them). Use git merge HEAD@{1} to fast forward them into master.

EDIT:

As noted in the comments, Git Ready has a great article on this.

git reflog and git reflog --all will give you the commit hashes of the mis-placed commits.

Git Ready: Reflog, Your Safety Net

Source: http://gitready.com/intermediate/2009/02/09/reflog-your-safety-net.html

Infinite Recursion with Jackson JSON and Hibernate JPA issue

VERY IMPORTANT: If you are using LOMBOK, make shure to exclude attributes of collections like Set, List, etc...

Like this:

@EqualsAndHashCode(exclude = {"attributeOfTypeList", "attributeOfTypeSet"})

Variable number of arguments in C++?

You probably shouldn't, and you can probably do what you want to do in a safer and simpler way. Technically to use variable number of arguments in C you include stdarg.h. From that you'll get the va_list type as well as three functions that operate on it called va_start(), va_arg() and va_end().

#include<stdarg.h>

int maxof(int n_args, ...)
{
    va_list ap;
    va_start(ap, n_args);
    int max = va_arg(ap, int);
    for(int i = 2; i <= n_args; i++) {
        int a = va_arg(ap, int);
        if(a > max) max = a;
    }
    va_end(ap);
    return max;
}

If you ask me, this is a mess. It looks bad, it's unsafe, and it's full of technical details that have nothing to do with what you're conceptually trying to achieve. Instead, consider using overloading or inheritance/polymorphism, builder pattern (as in operator<<() in streams) or default arguments etc. These are all safer: the compiler gets to know more about what you're trying to do so there are more occasions it can stop you before you blow your leg off.

How to select top n rows from a datatable/dataview in ASP.NET

public DataTable TopDataRow(DataTable dt, int count)
    {
        DataTable dtn = dt.Clone();
        int i = 0;
        foreach (DataRow row in dt.Rows)
        {
            if (i < count)
            {
                dtn.ImportRow(row);
                i++;
            }
            if (i > count)
                break;
        }
        return dtn;
    }

Documentation for using JavaScript code inside a PDF file

I'm pretty sure it's an Adobe standard, bearing in mind the whole PDF standard is theirs to begin with; despite being open now.

My guess would be no for all PDF viewers supporting it, as some definitely will not have a JS engine. I doubt you can rely on full support outside the most recent versions of Acrobat (Reader). So I guess it depends on how you imagine it being used, if mainly via a browser display, then the majority of the market is catered for by Acrobat (Reader) and Chrome's built-in viewer - dare say there is documentation on whether Chrome's PDF viewer supports JS fully.

rand() returns the same number each time the program is run

You are not seeding the number.

Use This:

#include <iostream>
#include <ctime>

using namespace std;

int main()
{
    srand(static_cast<unsigned int>(time(0)));
    cout << (rand() % 100) << endl;
    return 0;
}

You only need to seed it once though. Basically don't seed it every random number.

Node.js Error: Cannot find module express

Check if you have installed express module. If not, use this command:

npm install express

and if your node_modules directory is in another place, set NODE_PATH envirnment variable:

set NODE_PATH=your\directory\to\node_modules;%NODE_PATH%

How do I uniquely identify computers visiting my web site?

These people have developed a fingerprinting method for recognising a user with a high level of accuracy:

https://panopticlick.eff.org/static/browser-uniqueness.pdf

We investigate the degree to which modern web browsers are subject to “device fingerprinting” via the version and configuration information that they will transmit to websites upon request. We implemented one possible fingerprinting algorithm, and collected these fingerprints from a large sample of browsers that visited our test side, panopticlick.eff.org. We observe that the distribution of our finger- print contains at least 18.1 bits of entropy, meaning that if we pick a browser at random, at best we expect that only one in 286,777 other browsers will share its fingerprint. Among browsers that support Flash or Java, the situation is worse, with the average browser carrying at least 18.8 bits of identifying information. 94.2% of browsers with Flash or Java were unique in our sample.

By observing returning visitors, we estimate how rapidly browser fingerprints might change over time. In our sample, fingerprints changed quite rapidly, but even a simple heuristic was usually able to guess when a fingerprint was an “upgraded” version of a previously observed browser’s fingerprint, with 99.1% of guesses correct and a false positive rate of only 0.86%.

We discuss what privacy threat browser fingerprinting poses in practice, and what countermeasures may be appropriate to prevent it. There is a tradeoff between protection against fingerprintability and certain kinds of debuggability, which in current browsers is weighted heavily against privacy. Paradoxically, anti-fingerprinting privacy technologies can be self- defeating if they are not used by a sufficient number of people; we show that some privacy measures currently fall victim to this paradox, but others do not...

Windows cannot find 'http:/.127.0.0.1:%HTTPPORT%/apex/f?p=4950'. Make sure you typed the name correctly, and then try again

I was also facing this issue

Error- Windows cannot find 'http://127.0.01:%HTTPPORT%/apex/f?p=4950'. Make sure you typed the name correctly, and then try again

After some research work, I found out that my HTTPPORT ie. 8080 was occupied by Apace HTTP Server and hence connection by OracleServiceXE could not be established.

What I did to solve this issue was :

  1. Go to Windows -> Services, found out Apache2.4 and manually stopped it to free my 8080 port.
  2. Clicked on Start Database, and I received message :

The OracleServiceXE service is starting.............. The OracleServiceXE service was started successfully.

  1. Manually entered http://127.0.0.1:8080/apex/f?p=4950 url to my browser which auto redirected me to http://127.0.0.1:8080/apex/f?p=4950:1:3763261197573303

That's it my issue got resolved.

In order to remember this new url and make sure that next time whenever I hit Get Started I should be redirected to http://127.0.0.1:8080/apex/f?p=4950:1:3763261197573303 instead of http://127.0.0.1:8080/apex/f?p=4950, what I did was :

  1. Browse to Directory:\OracleDatabase\app\oracle\product\11.2.0\server and search for Get_Started.html.
  2. Right Click on Get_Started.html and select Properties
  3. Modify your url and click Apply

Hope this Helps.

How do I use CSS with a ruby on rails application?

If you are using rails > 3 version, then there is a concept called asset pipeline. You could add your CSS to

app/assets/stylesheets

then it will automatically be picked up by the app. (this is useful as rails will automatically compress the CSS files)

read more here about the asset pipeline