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rnoise_c - routine de calcul de nombre aléatoire de Rayleigh

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/* rnoise_c subroutine
 * Rayleigh noise generator
 *
 * Copyright (C) 2007-2011 Alan Layec
 *
 * This file is part of modnumlib.
 *
 * modnumlib 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.
 *
 * modnumlib 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 modnumlib; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

/* REVISION HISTORY :
 * $Log$
 */

#include <math.h>
#include <stdlib.h>  /*pour RAND_MAX*/

#include "modnum_lib.h"

/* rnoise_c routine de calcul d'échantillons bruités de Rayleigh
 *
 * Entrées :
 * n   : dimension 1 de la matrice de sortie (scalaire)
 * m   : dimension 2 de la matrice de sortie (scalaire)
 * sig  : parametre (scalaire)
 * Sorties :
 * y : matrice de sortie
 *
 * dépendances
 * math.h
 */

void rnoise_c(int *n,int *m,double *sig,double *y)
{
 /*déclaration des variables*/
 int i,l;
 double rand_m,rand1;

 int ind_y;

 /*récupération de la valeur de RAND_MAX*/
 rand_m=RAND_MAX;

 for(l=0;l<(*m);l++) {

   ind_y = (*n)*l;

   for(i=0;i<(*n);i++) {
     /*calcul rand1*/
     rand1=rand()/rand_m;

     /*test rand1*/
     while((rand1<=0)||(rand1>=1)) rand1=rand()/rand_m;

     /*Calcul sortie*/
     y[ind_y+i]=sqrt(2*pow((*sig),2)*log(1/(1e-5+1-rand1)));
   }
 }
 return;
}

Auteurs

A. Layec