You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
106 lines
2.7 KiB
C
106 lines
2.7 KiB
C
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <math.h>
|
|
#include "geostat.h"
|
|
|
|
|
|
/*FAST FOURIER TRANSFORM MOVING AVERAGE METHOD */
|
|
/*Turns a Gaussian white noise vector into a */
|
|
/*spatially correlated vector */
|
|
/*input: */
|
|
/*variogram: structure defining the variogram */
|
|
/* model */
|
|
/*grid: structure defining the grid */
|
|
/*n: vector with the number of cells along the */
|
|
/* X, Y and Z axes for the underlying grid */
|
|
/* i = [0 1 2] */
|
|
/* --> 0 0 0 : n will be computed and */
|
|
/* updated as output */
|
|
/* --> nx ny nz: these dimensions are used */
|
|
/*realin: structure defining a realization - */
|
|
/* must be a Gaussian white noise */
|
|
/*output: */
|
|
/*realout: structure defining a realization - */
|
|
|
|
void FFTMA2(struct vario_mod variogram,struct grid_mod grid,int n[3],struct realization_mod *realin,struct realization_mod *realout)
|
|
{
|
|
int NTOT,i,j,k,NMAX,NDIM,ntot,nmax,NXYZ,nxyz,maille0,maille1;
|
|
int solver;
|
|
double temp;
|
|
double *ireal,*covar,*workr,*worki,*realization;
|
|
|
|
/*covariance axis normalization*/
|
|
axes(variogram.ap,variogram.scf,variogram.Nvario);
|
|
|
|
/*pseudo-grid definition*/
|
|
cgrid(variogram,grid,n);
|
|
|
|
/*constant definition*/
|
|
NTOT = n[0]*n[1]*n[2];
|
|
ntot = NTOT+1;
|
|
NMAX = n[0];
|
|
NDIM = 3;
|
|
for (i=1;i<3;i++) {
|
|
if (n[i] > NMAX)
|
|
NMAX = n[i];
|
|
if (n[i] == 1)
|
|
NDIM--;
|
|
}
|
|
nmax = NMAX+1;
|
|
NXYZ = grid.NX*grid.NY*grid.NZ;
|
|
nxyz = NXYZ+1;
|
|
|
|
/*array initialization*/
|
|
covar = (double *) malloc(ntot * sizeof(double));
|
|
testmemory(covar);
|
|
|
|
ireal = (double *) malloc(ntot * sizeof(double));
|
|
testmemory(ireal);
|
|
|
|
realization = (double *) malloc(ntot * sizeof(double));
|
|
testmemory(realization);
|
|
|
|
workr = (double *) malloc(nmax * sizeof(double));
|
|
testmemory(workr);
|
|
|
|
worki = (double *) malloc(nmax * sizeof(double));
|
|
testmemory(worki);
|
|
|
|
/*covariance function creation*/
|
|
covariance(covar,variogram,grid,n);
|
|
|
|
/*power spectrum*/
|
|
fourt(covar,ireal,n,NDIM,1,0,workr,worki);
|
|
|
|
/*organization of the input Gaussian white noise*/
|
|
solver=0;
|
|
prebuild_gwn(grid,n,realin,realization,solver);
|
|
|
|
/*forward fourier transform of the GWN*/
|
|
fourt(realization,ireal,n,NDIM,1,0,workr,worki);
|
|
|
|
/* build realization in spectral domain */
|
|
build_real(n,NTOT,covar,realization,ireal);
|
|
|
|
free(covar);
|
|
|
|
/*backward fourier transform*/
|
|
fourt(realization,ireal,n,NDIM,0,1,workr,worki);
|
|
|
|
|
|
free(ireal);
|
|
free(workr);
|
|
free(worki);
|
|
|
|
/*output realization*/
|
|
clean_real(realin,n,grid,realization,realout);
|
|
|
|
free(realization);
|
|
|
|
return;
|
|
}
|
|
|
|
|
|
|
|
|