NFFT 3.5.3alpha
reconstruct_data_inh_nnfft.c
1/*
2 * Copyright (c) 2002, 2017 Jens Keiner, Stefan Kunis, Daniel Potts
3 *
4 * This program is free software; you can redistribute it and/or modify it under
5 * the terms of the GNU General Public License as published by the Free Software
6 * Foundation; either version 2 of the License, or (at your option) any later
7 * version.
8 *
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
11 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
12 * details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc., 51
16 * Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
17 */
18#include <stdlib.h>
19#include <math.h>
20#include <limits.h>
21#include <complex.h>
22
23#include "nfft3.h"
24
25#ifndef MAX
26#define MAX(a,b) (((a)>(b))?(a):(b))
27#endif
28
38static void reconstruct(char* filename,int N,int M,int iteration, int weight)
39{
40 int j,k,l; /* some variables */
41 nnfft_plan my_plan; /* plan for the two dimensional nfft */
42 solver_plan_complex my_iplan; /* plan for the two dimensional infft */
43 FILE* fin; /* input file */
44 FILE* finh;
45 FILE* ftime;
46 FILE* fout_real; /* output file */
47 FILE* fout_imag; /* output file */
48 int my_N[3],my_n[3]; /* to init the nfft */
49 double t0, t1;
50 double t,epsilon=0.0000003; /* epsilon is a the break criterium for
51 the iteration */
52 unsigned infft_flags = CGNR | PRECOMPUTE_DAMP; /* flags for the infft*/
53 double time,min_time,max_time,min_inh,max_inh;
54 double real,imag;
55 double *w;
56
57 double Ts;
58 double W;
59 int N3;
60 int m=2;
61 double sigma = 1.25;
62
63 w = (double*)nfft_malloc(N*N*sizeof(double));
64
65 ftime=fopen("readout_time.dat","r");
66 finh=fopen("inh.dat","r");
67
68 min_time=INT_MAX; max_time=INT_MIN;
69 for(j=0;j<M;j++)
70 {
71 fscanf(ftime,"%le ",&time);
72 if(time<min_time)
73 min_time = time;
74 if(time>max_time)
75 max_time = time;
76 }
77
78 fclose(ftime);
79
80 Ts=(min_time+max_time)/2.0;
81
82 min_inh=INT_MAX; max_inh=INT_MIN;
83 for(j=0;j<N*N;j++)
84 {
85 fscanf(finh,"%le ",&w[j]);
86 if(w[j]<min_inh)
87 min_inh = w[j];
88 if(w[j]>max_inh)
89 max_inh = w[j];
90 }
91 fclose(finh);
92
93 N3=ceil((MAX(fabs(min_inh),fabs(max_inh))*(max_time-min_time)/2.0)*4);
94
95
96 W=MAX(fabs(min_inh),fabs(max_inh))*2.0;
97
98 fprintf(stderr,"3: %i %e %e %e %e %e %e\n",N3,W,min_inh,max_inh,min_time,max_time,Ts);
99
100 /* initialise my_plan */
101 my_N[0]=N;my_n[0]=ceil(N*sigma);
102 my_N[1]=N; my_n[1]=ceil(N*sigma);
103 my_N[2]=N3; my_n[2]=ceil(N3*sigma);
104 nnfft_init_guru(&my_plan, 3, N*N, M, my_N,my_n,m,
106
107 /* precompute lin psi if set */
108 if(my_plan.nnfft_flags & PRE_LIN_PSI)
109 nnfft_precompute_lin_psi(&my_plan);
110
111 /* set the flags for the infft*/
112 if (weight)
113 infft_flags = infft_flags | PRECOMPUTE_WEIGHT;
114
115 /* initialise my_iplan, advanced */
116 solver_init_advanced_complex(&my_iplan,(nfft_mv_plan_complex*)(&my_plan), infft_flags );
117
118 /* get the weights */
119 if(my_iplan.flags & PRECOMPUTE_WEIGHT)
120 {
121 fin=fopen("weights.dat","r");
122 for(j=0;j<my_plan.M_total;j++)
123 {
124 fscanf(fin,"%le ",&my_iplan.w[j]);
125 }
126 fclose(fin);
127 }
128
129 /* get the damping factors */
130 if(my_iplan.flags & PRECOMPUTE_DAMP)
131 {
132 for(j=0;j<N;j++){
133 for(k=0;k<N;k++) {
134 int j2= j-N/2;
135 int k2= k-N/2;
136 double r=sqrt(j2*j2+k2*k2);
137 if(r>(double) N/2)
138 my_iplan.w_hat[j*N+k]=0.0;
139 else
140 my_iplan.w_hat[j*N+k]=1.0;
141 }
142 }
143 }
144
145 /* open the input file */
146 fin=fopen(filename,"r");
147 ftime=fopen("readout_time.dat","r");
148
149 for(j=0;j<my_plan.M_total;j++)
150 {
151 fscanf(fin,"%le %le %le %le ",&my_plan.x[3*j+0],&my_plan.x[3*j+1],&real,&imag);
152 my_iplan.y[j]=real+ _Complex_I*imag;
153 fscanf(ftime,"%le ",&my_plan.x[3*j+2]);
154
155 my_plan.x[3*j+2] = (my_plan.x[3*j+2]-Ts)*W/N3;
156 }
157
158 for(j=0;j<N;j++)
159 {
160 for(l=0;l<N;l++)
161 {
162 my_plan.v[3*(N*j+l)+0]=(((double) j) -(((double) N)/2.0))/((double) N);
163 my_plan.v[3*(N*j+l)+1]=(((double) l) -(((double) N)/2.0))/((double) N);
164 my_plan.v[3*(N*j+l)+2] = w[N*j+l]/W ;
165 }
166 }
167
168 /* precompute psi */
169 if(my_plan.nnfft_flags & PRE_PSI) {
170 nnfft_precompute_psi(&my_plan);
171 if(my_plan.nnfft_flags & PRE_FULL_PSI)
173 }
174
175 if(my_plan.nnfft_flags & PRE_PHI_HUT)
176 nnfft_precompute_phi_hut(&my_plan);
177
178 /* init some guess */
179 for(k=0;k<my_plan.N_total;k++)
180 {
181 my_iplan.f_hat_iter[k]=0.0;
182 }
183
184 t0 = nfft_clock_gettime_seconds();
185
186 /* inverse trafo */
187 solver_before_loop_complex(&my_iplan);
188 for(l=0;l<iteration;l++)
189 {
190 /* break if dot_r_iter is smaller than epsilon*/
191 if(my_iplan.dot_r_iter<epsilon)
192 break;
193 fprintf(stderr,"%e, %i of %i\n",sqrt(my_iplan.dot_r_iter),
194 l+1,iteration);
195 solver_loop_one_step_complex(&my_iplan);
196 }
197
198 t1 = nfft_clock_gettime_seconds();
199 t = t1-t0;
200
201 fout_real=fopen("output_real.dat","w");
202 fout_imag=fopen("output_imag.dat","w");
203
204 for(k=0;k<my_plan.N_total;k++) {
205
206 my_iplan.f_hat_iter[k]*=cexp(2.0*_Complex_I*M_PI*Ts*w[k]);
207
208 fprintf(fout_real,"%le ", creal(my_iplan.f_hat_iter[k]));
209 fprintf(fout_imag,"%le ", cimag(my_iplan.f_hat_iter[k]));
210 }
211
212
213 fclose(fout_real);
214 fclose(fout_imag);
215
216
217 /* finalize the infft */
218 solver_finalize_complex(&my_iplan);
219
220 /* finalize the nfft */
221 nnfft_finalize(&my_plan);
222
223 nfft_free(w);
224}
225
226int main(int argc, char **argv)
227{
228 if (argc <= 5) {
229 printf("usage: ./reconstruct_data_inh_nnfft FILENAME N M ITER WEIGHTS\n");
230 return 1;
231 }
232
233 reconstruct(argv[1],atoi(argv[2]),atoi(argv[3]),atoi(argv[4]),atoi(argv[5]));
234
235 return 1;
236}
237/* \} */
static void reconstruct(char *filename, int N, int M, int iteration, int weight)
reconstruct
#define MALLOC_F_HAT
Definition nfft3.h:194
#define MALLOC_X
Definition nfft3.h:193
#define PRE_FULL_PSI
Definition nfft3.h:192
#define PRE_PSI
Definition nfft3.h:191
#define MALLOC_F
Definition nfft3.h:195
#define PRE_LIN_PSI
Definition nfft3.h:189
#define PRE_PHI_HUT
Definition nfft3.h:187
#define MALLOC_V
Definition nfft3.h:429
#define CGNR
Definition nfft3.h:808
#define PRECOMPUTE_DAMP
Definition nfft3.h:812
#define PRECOMPUTE_WEIGHT
Definition nfft3.h:811
Header file for the nfft3 library.
void nnfft_precompute_lin_psi(nnfft_plan *ths_plan)
create a lookup table
Definition nnfft.c:367
void nnfft_precompute_full_psi(nnfft_plan *ths_plan)
computes all entries of B explicitly
Definition nnfft.c:424
void nnfft_precompute_phi_hut(nnfft_plan *ths_plan)
initialisation of direct transform
Definition nnfft.c:347
void * nfft_malloc(size_t n)
void nfft_free(void *p)
data structure for an NNFFT (nonequispaced in time and frequency fast Fourier transform) plan with do...
Definition nfft3.h:425
double * v
nodes (in fourier domain)
Definition nfft3.h:425
NFFT_INT M_total
Total number of samples.
Definition nfft3.h:425
unsigned nnfft_flags
flags for precomputation, malloc
Definition nfft3.h:425
NFFT_INT N_total
Total number of Fourier coefficients.
Definition nfft3.h:425
double * x
nodes (in time/spatial domain)
Definition nfft3.h:425
data structure for an inverse NFFT plan with double precision
Definition nfft3.h:802
double * w
weighting factors
Definition nfft3.h:802
unsigned flags
iteration type
Definition nfft3.h:802
double * w_hat
damping factors
Definition nfft3.h:802
double dot_r_iter
weighted dotproduct of r_iter
Definition nfft3.h:802
fftw_complex * y
right hand side, samples
Definition nfft3.h:802
fftw_complex * f_hat_iter
iterative solution
Definition nfft3.h:802