reconstruct_data_2d1d.c
/*
* Copyright (c) 2002, 2017 Jens Keiner, Stefan Kunis, Daniel Potts
*
* 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., 51
* Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include "config.h"
#include <stdlib.h>
#include <math.h>
#ifdef HAVE_COMPLEX_H
#include <complex.h>
#endif
#include "nfft3.h"
static void reconstruct(char* filename,int N,int M,int Z,int iteration, int weight, fftw_complex *mem)
{
int j,k,l,z; /* some variables */
double real,imag; /* to read the real and imag part of a complex number */
nfft_plan my_plan; /* plan for the two dimensional nfft */
solver_plan_complex my_iplan; /* plan for the two dimensional infft */
FILE* fin; /* input file */
int my_N[2],my_n[2]; /* to init the nfft */
double tmp, epsilon=0.0000003;/* tmp to read the obsolent z from the input file
epsilon is the break criterium for
the iteration */
unsigned infft_flags = CGNR | PRECOMPUTE_DAMP; /* flags for the infft */
/* initialise my_plan */
my_N[0]=N;my_n[0]=ceil(N*1.2);
my_N[1]=N; my_n[1]=ceil(N*1.2);
nfft_init_guru(&my_plan, 2, my_N, M/Z, my_n, 6, PRE_PHI_HUT| PRE_PSI|
MALLOC_X| MALLOC_F_HAT| MALLOC_F|
FFTW_INIT,
FFTW_MEASURE);
/* precompute lin psi if set */
if(my_plan.flags & PRE_LIN_PSI)
nfft_precompute_lin_psi(&my_plan);
/* set the flags for the infft*/
if (weight)
infft_flags = infft_flags | PRECOMPUTE_WEIGHT;
/* initialise my_iplan, advanced */
solver_init_advanced_complex(&my_iplan,(nfft_mv_plan_complex*)(&my_plan), infft_flags );
/* get the weights */
if(my_iplan.flags & PRECOMPUTE_WEIGHT)
{
fin=fopen("weights.dat","r");
for(j=0;j<my_plan.M_total;j++)
{
fscanf(fin,"%le ",&my_iplan.w[j]);
}
fclose(fin);
}
/* get the damping factors */
if(my_iplan.flags & PRECOMPUTE_DAMP)
{
for(j=0;j<N;j++){
for(k=0;k<N;k++) {
int j2= j-N/2;
int k2= k-N/2;
double r=sqrt(j2*j2+k2*k2);
if(r>(double) N/2)
my_iplan.w_hat[j*N+k]=0.0;
else
my_iplan.w_hat[j*N+k]=1.0;
}
}
}
/* open the input file */
fin=fopen(filename,"r");
/* For every Layer*/
for(z=0;z<Z;z++) {
/* read x,y,freal and fimag from the knots */
for(j=0;j<my_plan.M_total;j++)
{
fscanf(fin,"%le %le %le %le %le ",&my_plan.x[2*j+0],&my_plan.x[2*j+1], &tmp,
&real,&imag);
my_iplan.y[j] = real + _Complex_I*imag;
}
/* precompute psi if set just one time because the knots equal each plane */
if(z==0 && my_plan.flags & PRE_PSI)
nfft_precompute_psi(&my_plan);
/* precompute full psi if set just one time because the knots equal each plane */
if(z==0 && my_plan.flags & PRE_FULL_PSI)
nfft_precompute_full_psi(&my_plan);
/* init some guess */
for(k=0;k<my_plan.N_total;k++)
my_iplan.f_hat_iter[k]=0.0;
/* inverse trafo */
solver_before_loop_complex(&my_iplan);
for(l=0;l<iteration;l++)
{
/* break if dot_r_iter is smaller than epsilon*/
if(my_iplan.dot_r_iter<epsilon)
break;
fprintf(stderr,"%e, %i of %i\n",sqrt(my_iplan.dot_r_iter),
iteration*z+l+1,iteration*Z);
solver_loop_one_step_complex(&my_iplan);
}
for(k=0;k<my_plan.N_total;k++) {
/* write every slice in the memory.
here we make an fftshift direct */
mem[(Z*N*N/2+z*N*N+ k)%(Z*N*N)] = my_iplan.f_hat_iter[k];
}
}
fclose(fin);
/* finalize the infft */
solver_finalize_complex(&my_iplan);
/* finalize the nfft */
nfft_finalize(&my_plan);
}
static void print(int N,int M,int Z, fftw_complex *mem)
{
int i,j;
FILE* fout_real;
FILE* fout_imag;
fout_real=fopen("output_real.dat","w");
fout_imag=fopen("output_imag.dat","w");
for(i=0;i<Z;i++) {
for (j=0;j<N*N;j++) {
fprintf(fout_real,"%le ",creal(mem[(Z*N*N/2+i*N*N+ j)%(Z*N*N)]) /Z);
fprintf(fout_imag,"%le ",cimag(mem[(Z*N*N/2+i*N*N+ j)%(Z*N*N)]) /Z);
}
fprintf(fout_real,"\n");
fprintf(fout_imag,"\n");
}
fclose(fout_real);
fclose(fout_imag);
}
int main(int argc, char **argv)
{
fftw_complex *mem;
fftw_plan plan;
int N,M,Z;
if (argc <= 6) {
printf("usage: ./reconstruct FILENAME N M Z ITER WEIGHTS\n");
return 1;
}
N=atoi(argv[2]);
M=atoi(argv[3]);
Z=atoi(argv[4]);
/* Allocate memory to hold every layer in memory after the
2D-infft */
mem = (fftw_complex*) nfft_malloc(sizeof(fftw_complex) * atoi(argv[2]) * atoi(argv[2]) * atoi(argv[4]));
/* Create plan for the 1d-ifft */
plan = fftw_plan_many_dft(1, &Z, N*N,
mem, NULL,
N*N, 1,
mem, NULL,
N*N,1 ,
FFTW_BACKWARD, FFTW_MEASURE);
/* execute the 2d-infft's */
reconstruct(argv[1],N,M,Z,atoi(argv[5]),atoi(argv[6]),mem);
/* execute the 1d-fft's */
fftw_execute(plan);
/* write the memory back in files */
print(N,M,Z, mem);
/* free memory */
nfft_free(mem);
fftw_destroy_plan(plan);
return 1;
}
/* \} */
print
static void print(int N, int M, int Z, fftw_complex *mem)
print writes the memory back in a file output_real.dat for the real part and output_imag....
Definition reconstruct_data_2d1d.c:153
reconstruct
static void reconstruct(char *filename, int N, int M, int Z, int iteration, int weight, fftw_complex *mem)
reconstruct makes an inverse 2d-nfft for every slice
Definition reconstruct_data_2d1d.c:37
MALLOC_F_HAT
#define MALLOC_F_HAT
Definition nfft3.h:188
MALLOC_X
#define MALLOC_X
Definition nfft3.h:187
nfft_precompute_lin_psi
void nfft_precompute_lin_psi(nfft_plan *ths)
nfft_finalize
void nfft_finalize(nfft_plan *ths)
PRE_FULL_PSI
#define PRE_FULL_PSI
Definition nfft3.h:186
PRE_PSI
#define PRE_PSI
Definition nfft3.h:185
MALLOC_F
#define MALLOC_F
Definition nfft3.h:189
PRE_LIN_PSI
#define PRE_LIN_PSI
Definition nfft3.h:183
FFTW_INIT
#define FFTW_INIT
Definition nfft3.h:191
PRE_PHI_HUT
#define PRE_PHI_HUT
Definition nfft3.h:181
nfft_precompute_psi
void nfft_precompute_psi(nfft_plan *ths)
nfft_precompute_full_psi
void nfft_precompute_full_psi(nfft_plan *ths)
CGNR
#define CGNR
Definition nfft3.h:802
PRECOMPUTE_DAMP
#define PRECOMPUTE_DAMP
Definition nfft3.h:806
PRECOMPUTE_WEIGHT
#define PRECOMPUTE_WEIGHT
Definition nfft3.h:805
nfft3.h
Header file for the nfft3 library.
nfft_malloc
void * nfft_malloc(size_t n)
nfft_free
void nfft_free(void *p)
nfft_mv_plan_complex
Definition nfft3.h:177
nfft_plan
solver_plan_complex
data structure for an inverse NFFT plan with double precision
Definition nfft3.h:796
solver_plan_complex::w
double * w
weighting factors
Definition nfft3.h:796
solver_plan_complex::flags
unsigned flags
iteration type
Definition nfft3.h:796
solver_plan_complex::w_hat
double * w_hat
damping factors
Definition nfft3.h:796
solver_plan_complex::dot_r_iter
double dot_r_iter
weighted dotproduct of r_iter
Definition nfft3.h:796
solver_plan_complex::y
fftw_complex * y
right hand side, samples
Definition nfft3.h:796
solver_plan_complex::f_hat_iter
fftw_complex * f_hat_iter
iterative solution
Definition nfft3.h:796