random.cc

Short description: A MAX-MIN Ant System (MMAS) implemented in the Hyper-Cube Framework for the appli

/***************************************************************************
                          Random.cc  -  description
                             -------------------
    begin                : Fri Nov 10 2000
    copyright            : (C) 2000 by Christian Blum
    email                : [e-mail]
 ***************************************************************************/

/***************************************************************************
    Program's name: hc-mmas-ubqp

    Ant Colony Optimization algorithm to tackle 
    Unary Binary Quadratic Programming

    Copyright (C) 2003  Christian Blum

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    Author's contact details: 

    email: [e-mail]
    mail address: Universite Libre de Bruxelles, IRIDIA,
                  Av. Franklin Roosevelt 50, CP 194/6,
                  B-1050 Brussels, Belgium

 ***************************************************************************/

#include "Random.h"
#include <stdio.h>
#define VERBOSE(x) x
#define VERYVERBOSE(x)

/* pseudo-random number generator as proposed in numerical recipes in C 
   Input:   a long value; has to be the seed variable
   Output:  a pseudo-random number uniformly distributed in [0,1]
   Side effects: changes the value of the input variable, must be this way
*/
double Random::ran01( long *idum )
{
  long k;
  double ans;

  k =(*idum)/IQ;
  *idum = IA * (*idum - k * IQ) - IR * k;
  if (*idum < 0 ) *idum += IM;
  ans = AM * (*idum);
  return ans;
}

double Random::gasdev(long *idum)
{
  //double ran01(long *idum);
	static int iset=0;
	static double gset;
	double fac,rsq,v1,v2;

	if  (iset == 0) {
		do {
		  v1=2.0*ran01(idum)-1.0;
		  v2=2.0*ran01(idum)-1.0;
		  //v1 = ran01(idum);
		  //v2 = ran01(idum);
		  rsq=v1*v1+v2*v2;
		} while (rsq >= 1.0 || rsq == 0.0);
		fac=sqrt(-2.0*log(rsq)/rsq);
		gset=v1*fac;
		iset=1;
		return v2*fac;
	} else {
		iset=0;
		return gset;
	}
}



long int* Random::generate_array(const int& size) {
   long int  i, j, help;
   long int  *v;

   v = (long int*) malloc( size * sizeof(long int) );

   for ( i = 0 ; i < size; i++ ) 
     v[i] = i;

   for ( i = 0 ; i < size-1 ; i++) {
     j = (long int) ( ran01( &seed ) * (size - i)); 
     assert( i + j < size );
     help = v[i];
     v[i] = v[i+j];
     v[i+j] = help;
   }
   VERYVERBOSE ( printf("Random vector:\n");
   for (i = 0 ; i < size ; i++ ) 
     printf(" %ld ",v[i]);
   printf("\n"); )
   return v;
}