Re: help with mersenne_twister

17 Mar 2003

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-----Original Message-----
From: Jon Agiato [mailto:JonAgiato@n...]
I am having difficulty in understanding the documentation 
regarding 
the use of the pseudo-random number generators in 
boost::random.  
Below, I have created a small sample program of the type I am
--- In Boost-Users@yahoogroups.com, scleary@j... wrote:
trying
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to create in order to use the various classes in boost::random 
with 
Diehard (requires a binary file of 32 bit integers for 
testing).  
This program does not compile as it says that mersenne_twister 
requires template arguments.  I understand what that means of 
course, but am unsure as to what arguments should go in there.  
I am 
using MSVC++ 7.0 and would really apprechiate any assistance.  
Thanks!
The Boost.Random library defines fully-generic random number 
generator
algorithms, e.g., boost::random::mersenne_twister,
boost::random::linear_congruential, etc.  These are only for 
advanced users.
Hello Steve, and thank you for your kind help.  I am trying to use 
the boost library as part of a project in which I demonstrate the 
validity of various random number generation algorithms and 
methodologies.  I wanted to use boost to demonstrate what can be 
achieved through top class C++ generic programming.
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The Boost.Random library also provides specializations of those
generic
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random number generator algorithms for use by normal users.  e.g.,
boost::mt19937 and boost::mt11213b are both specializations of the 
Mersenne
twister; and boost::minstd_rand is a specialization of the linear
congruential algorithm.
So, unless you have really exceptional random number requirements, 
you
should be using boost::mt19937 instead of 
boost::random::mersenne_twister:
I used mt19937 as you directed and my example did compile but when I 
ran the binary file through Diehard it failed every single test 
every time.  I am sure this can not be due to the algorithm, but I 
can not pinpoint what I could be doing in error.  Here is the code I 
used to create a binary file for diehard:

#include <iostream>
using std::cout;
using std::cin;

#include <cstdlib>

#include 
using boost::mt19937;

#include <iomanip>
using std::ios;

#include <fstream>
using std::ofstream;

int main()
{
	ofstream file("MTRNG.bin", ios::binary);
	const unsigned int N = 30000;
	unsigned int i = 0;
	mt19937 MT;
	for(; i != N; ++i)
	{
		file << MT;
	}

	cout << "Operation complete.  Press enter to exit...";
	cin.get();

	return EXIT_SUCCESS;
}
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using boost::random::mersenne_twister;
using boost::mt19937;
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mersenne_twister MT;
mt19937 MT;
Then your example should compile.
  -Steve
I was intending on using boost::random to demonstrate various 
deterministic and non-deterministic RNGs and their validity as far 
as randomness using Diehard.  I am thinking either I am doing 
something wrong, or maybe I do require the use of the advanced RNG 
classes boost offers.  Does anyone have any ideas?

Again, thanks for any and all assistance.

Jon Agiato
JonAgiato@nyc.rr.com

Re: help with mersenne_twister

agiatojon