static void test_accuracy(){
rand_t rstat;
int seed=4;
double r0=0.2;
double dx=1./64.;
long N=1+64;
long nx=N;
long ny=N;
seed_rand(&rstat, seed);
map_t *atm=mapnew(nx, ny, dx, dx,NULL);
for(long i=0; i<nx*ny; i++){
atm->p[i]=randn(&rstat);
}
map_t *atm2=mapnew(nx, ny, dx, dx,NULL);
for(long i=0; i<nx*ny; i++){
atm2->p[i]=randn(&rstat);
}
mapwrite(atm, "atm_rand.bin");
mapwrite(atm2, "atm2_rand.bin");
fractal_do((dmat*)atm, dx, r0,L0,ninit);
mapwrite(atm, "atm_frac.bin");
fractal_inv((dmat*)atm, dx, r0,L0,ninit);
mapwrite(atm, "atm_frac_inv.bin");
fractal_trans((dmat*)atm2, dx, r0,L0,ninit);
mapwrite(atm2, "atm2_frac_trans.bin");
fractal_inv_trans((dmat*)atm2, dx, r0,L0,ninit);
mapwrite(atm2, "atm2_frac_inv_trans.bin");
/*
atm2 is u, atm is v, now comparing u'Av against v'A'u. they should be the same.
A^-1Av should be the same as v
A'^-1A'u should be the same as u.
*/
dmat *u=dread("atm2_rand.bin");
dmat *Atu=dread("atm2_frac_trans.bin");
dmat *Av=dread("atm_frac.bin");
dmat *v=dread("atm_rand.bin");
double dot1=dotdbl(u->p, Av->p, NULL, nx*ny);
double dot2=dotdbl(v->p, Atu->p, NULL, nx*ny);
info("dot1=%g, dot2=%g, diff=%g\n", dot1, dot2, dot1-dot2);
dmat *u2=dread("atm2_frac_inv_trans.bin");
dmat *v2=dread("atm_frac_inv.bin");
double d1=ddiff(u, u2);
double d2=ddiff(v, v2);
info("d1=%g, d2=%g\n", d1, d2);
}
/**
normalize vector to sum to norm;*/
void normalize_sum(double *p, long nloc, double norm){
if(!nloc) return;
double ss=norm/dotdbl(p,NULL,NULL,nloc);
for(int i=0; i<nloc; i++){
p[i]*=ss;
}
}
