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Random number generators

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Join Date: May 2009

Posts: 1

Reputation: somyasinha is an unknown quantity at this point

Solved Threads: 0

somyasinha somyasinha is offline

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Newbie Poster

Re: Random number generator's

Jul 6th, 2009

Hi,

How do I use the generator in the file? I keep randomc.h as a header file in the Visual c++ project. My project has several header files and several .cpp files, many of which require to use the random no. generator. I have copied all the files in the zip folder into the folder for my project files.
Do I write this in each file that uses the generator?

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
#ifndef MULTIFILE_PROJECT
// If compiled as a single file then include these cpp files, 
// If compiled as a project then compile and link in these cpp files.
   // Include code for the chosen random number generator:
   #include "mersenne.cpp"
   // define system specific user interface:
   #include "userintf.cpp"
#endif
 
 
#include <time.h>                      // define time()
#include "randomc.h"
#ifndef MULTIFILE_PROJECT
// If compiled as a single file then include these cpp files, 
// If compiled as a project then compile and link in these cpp files.
   // Include code for the chosen random number generator:
   #include "mersenne.cpp"
   // define system specific user interface:
   #include "userintf.cpp"
#endif


#include <time.h>                      // define time()
#include "randomc.h"

The compling is ok. But I get a lot of linking errors, e.g.,

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GABaseSolver.obj : error LNK2005: "private: void __thiscall CRandomMersenne::Init0(int)" (?Init0@CRandomMersenne@@AAEXH@Z) already defined in GA1DArraySolution.obj

Please help.

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Join Date: Apr 2009

Posts: 219

Reputation: NathanOliver is an unknown quantity at this point

Solved Threads: 37

NathanOliver NathanOliver is offline

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Posting Whiz in Training

Re: Random number generators

Jul 6th, 2009

in every header file it is a good idea to use inclusion guards. so to stop it from getting defined all the time just put

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 c++ Syntax (Toggle Plain Text) 
#ifndef RANDOMC_H
#define RANDOMC_H
//  all the code in randomc.h goes here
#endif
#ifndef RANDOMC_H
#define RANDOMC_H
//  all the code in randomc.h goes here
#endif

this will make sure that the file is only included the first time and every other time #include "randomc.h" is encountered the compiler will skip that file because it is already defined. I've found this makes things easier down the road and saves some debugging time.