![]() |
NFFT
3.3.2
|
00001 /* 00002 * Copyright (c) 2002, 2016 Jens Keiner, Stefan Kunis, Daniel Potts 00003 * 00004 * This program is free software; you can redistribute it and/or modify it under 00005 * the terms of the GNU General Public License as published by the Free Software 00006 * Foundation; either version 2 of the License, or (at your option) any later 00007 * version. 00008 * 00009 * This program is distributed in the hope that it will be useful, but WITHOUT 00010 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 00011 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more 00012 * details. 00013 * 00014 * You should have received a copy of the GNU General Public License along with 00015 * this program; if not, write to the Free Software Foundation, Inc., 51 00016 * Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. 00017 */ 00018 #include "config.h" 00019 00020 #include <stdlib.h> 00021 #include <math.h> 00022 #ifdef HAVE_COMPLEX_H 00023 #include <complex.h> 00024 #endif 00025 00026 #include "nfft3.h" 00027 00037 static void reconstruct(char* filename,int N,int M,int Z,int iteration, int weight, fftw_complex *mem) 00038 { 00039 int j,k,l,z; /* some variables */ 00040 double real,imag; /* to read the real and imag part of a complex number */ 00041 nfft_plan my_plan; /* plan for the two dimensional nfft */ 00042 solver_plan_complex my_iplan; /* plan for the two dimensional infft */ 00043 FILE* fin; /* input file */ 00044 int my_N[2],my_n[2]; /* to init the nfft */ 00045 double tmp, epsilon=0.0000003;/* tmp to read the obsolent z from the input file 00046 epsilon is the break criterium for 00047 the iteration */ 00048 unsigned infft_flags = CGNR | PRECOMPUTE_DAMP; /* flags for the infft */ 00049 00050 /* initialise my_plan */ 00051 my_N[0]=N;my_n[0]=ceil(N*1.2); 00052 my_N[1]=N; my_n[1]=ceil(N*1.2); 00053 nfft_init_guru(&my_plan, 2, my_N, M/Z, my_n, 6, PRE_PHI_HUT| PRE_PSI| 00054 MALLOC_X| MALLOC_F_HAT| MALLOC_F| 00055 FFTW_INIT| FFT_OUT_OF_PLACE, 00056 FFTW_MEASURE| FFTW_DESTROY_INPUT); 00057 00058 /* precompute lin psi if set */ 00059 if(my_plan.flags & PRE_LIN_PSI) 00060 nfft_precompute_lin_psi(&my_plan); 00061 00062 /* set the flags for the infft*/ 00063 if (weight) 00064 infft_flags = infft_flags | PRECOMPUTE_WEIGHT; 00065 00066 /* initialise my_iplan, advanced */ 00067 solver_init_advanced_complex(&my_iplan,(nfft_mv_plan_complex*)(&my_plan), infft_flags ); 00068 00069 /* get the weights */ 00070 if(my_iplan.flags & PRECOMPUTE_WEIGHT) 00071 { 00072 fin=fopen("weights.dat","r"); 00073 for(j=0;j<my_plan.M_total;j++) 00074 { 00075 fscanf(fin,"%le ",&my_iplan.w[j]); 00076 } 00077 fclose(fin); 00078 } 00079 00080 /* get the damping factors */ 00081 if(my_iplan.flags & PRECOMPUTE_DAMP) 00082 { 00083 for(j=0;j<N;j++){ 00084 for(k=0;k<N;k++) { 00085 int j2= j-N/2; 00086 int k2= k-N/2; 00087 double r=sqrt(j2*j2+k2*k2); 00088 if(r>(double) N/2) 00089 my_iplan.w_hat[j*N+k]=0.0; 00090 else 00091 my_iplan.w_hat[j*N+k]=1.0; 00092 } 00093 } 00094 } 00095 00096 /* open the input file */ 00097 fin=fopen(filename,"r"); 00098 00099 /* For every Layer*/ 00100 for(z=0;z<Z;z++) { 00101 00102 /* read x,y,freal and fimag from the knots */ 00103 for(j=0;j<my_plan.M_total;j++) 00104 { 00105 fscanf(fin,"%le %le %le %le %le ",&my_plan.x[2*j+0],&my_plan.x[2*j+1], &tmp, 00106 &real,&imag); 00107 my_iplan.y[j] = real + _Complex_I*imag; 00108 } 00109 00110 /* precompute psi if set just one time because the knots equal each plane */ 00111 if(z==0 && my_plan.flags & PRE_PSI) 00112 nfft_precompute_psi(&my_plan); 00113 00114 /* precompute full psi if set just one time because the knots equal each plane */ 00115 if(z==0 && my_plan.flags & PRE_FULL_PSI) 00116 nfft_precompute_full_psi(&my_plan); 00117 00118 /* init some guess */ 00119 for(k=0;k<my_plan.N_total;k++) 00120 my_iplan.f_hat_iter[k]=0.0; 00121 00122 /* inverse trafo */ 00123 solver_before_loop_complex(&my_iplan); 00124 for(l=0;l<iteration;l++) 00125 { 00126 /* break if dot_r_iter is smaller than epsilon*/ 00127 if(my_iplan.dot_r_iter<epsilon) 00128 break; 00129 fprintf(stderr,"%e, %i of %i\n",sqrt(my_iplan.dot_r_iter), 00130 iteration*z+l+1,iteration*Z); 00131 solver_loop_one_step_complex(&my_iplan); 00132 } 00133 for(k=0;k<my_plan.N_total;k++) { 00134 /* write every slice in the memory. 00135 here we make an fftshift direct */ 00136 mem[(Z*N*N/2+z*N*N+ k)%(Z*N*N)] = my_iplan.f_hat_iter[k]; 00137 } 00138 } 00139 00140 fclose(fin); 00141 00142 /* finalize the infft */ 00143 solver_finalize_complex(&my_iplan); 00144 00145 /* finalize the nfft */ 00146 nfft_finalize(&my_plan); 00147 } 00148 00153 static void print(int N,int M,int Z, fftw_complex *mem) 00154 { 00155 int i,j; 00156 FILE* fout_real; 00157 FILE* fout_imag; 00158 fout_real=fopen("output_real.dat","w"); 00159 fout_imag=fopen("output_imag.dat","w"); 00160 00161 for(i=0;i<Z;i++) { 00162 for (j=0;j<N*N;j++) { 00163 fprintf(fout_real,"%le ",creal(mem[(Z*N*N/2+i*N*N+ j)%(Z*N*N)]) /Z); 00164 fprintf(fout_imag,"%le ",cimag(mem[(Z*N*N/2+i*N*N+ j)%(Z*N*N)]) /Z); 00165 } 00166 fprintf(fout_real,"\n"); 00167 fprintf(fout_imag,"\n"); 00168 } 00169 00170 fclose(fout_real); 00171 fclose(fout_imag); 00172 } 00173 00174 int main(int argc, char **argv) 00175 { 00176 fftw_complex *mem; 00177 fftw_plan plan; 00178 int N,M,Z; 00179 00180 if (argc <= 6) { 00181 printf("usage: ./reconstruct FILENAME N M Z ITER WEIGHTS\n"); 00182 return 1; 00183 } 00184 00185 N=atoi(argv[2]); 00186 M=atoi(argv[3]); 00187 Z=atoi(argv[4]); 00188 00189 /* Allocate memory to hold every layer in memory after the 00190 2D-infft */ 00191 mem = (fftw_complex*) nfft_malloc(sizeof(fftw_complex) * atoi(argv[2]) * atoi(argv[2]) * atoi(argv[4])); 00192 00193 /* Create plan for the 1d-ifft */ 00194 plan = fftw_plan_many_dft(1, &Z, N*N, 00195 mem, NULL, 00196 N*N, 1, 00197 mem, NULL, 00198 N*N,1 , 00199 FFTW_BACKWARD, FFTW_MEASURE); 00200 00201 /* execute the 2d-infft's */ 00202 reconstruct(argv[1],N,M,Z,atoi(argv[5]),atoi(argv[6]),mem); 00203 00204 /* execute the 1d-fft's */ 00205 fftw_execute(plan); 00206 00207 /* write the memory back in files */ 00208 print(N,M,Z, mem); 00209 00210 /* free memory */ 00211 nfft_free(mem); 00212 fftw_destroy_plan(plan); 00213 return 1; 00214 } 00215 /* \} */