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reconstruct_data_inh_2d1d.c

00001 /*
00002  * Copyright (c) 2002, 2009 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 
00019 /* $Id: reconstruct_data_inh_2d1d.c 3198 2009-05-27 14:16:50Z keiner $ */
00020 
00021 #include <stdlib.h>
00022 #include <math.h>
00023 #include <limits.h>
00024 #include <complex.h>
00025 
00026 #include "nfft3.h"
00027 #include "nfft3util.h"
00028 
00035 void reconstruct(char* filename,int N,int M,int iteration , int weight)
00036 {
00037   int j,k,l;
00038   double time,min_time,max_time,min_inh,max_inh;
00039   double t,real,imag;
00040   double w,epsilon=0.0000003;     /* epsilon is a the break criterium for
00041                                    the iteration */;
00042   mri_inh_2d1d_plan my_plan;
00043   solver_plan_complex my_iplan;
00044   FILE* fp,*fw,*fout_real,*fout_imag,*finh,*ftime;
00045   int my_N[3],my_n[3];
00046   int flags = PRE_PHI_HUT| PRE_PSI |MALLOC_X| MALLOC_F_HAT|
00047                       MALLOC_F| FFTW_INIT| FFT_OUT_OF_PLACE;
00048   unsigned infft_flags = CGNR | PRECOMPUTE_DAMP;
00049 
00050   double Ts;
00051   double W,T;
00052   int N3;
00053   int m=2;
00054   double sigma = 1.25;
00055 
00056   ftime=fopen("readout_time.dat","r");
00057   finh=fopen("inh.dat","r");
00058 
00059   min_time=INT_MAX; max_time=INT_MIN;
00060   for(j=0;j<M;j++)
00061   {
00062     fscanf(ftime,"%le ",&time);
00063     if(time<min_time)
00064       min_time = time;
00065     if(time>max_time)
00066       max_time = time;
00067   }
00068 
00069   fclose(ftime);
00070 
00071   Ts=(min_time+max_time)/2.0;
00072 
00073 
00074   min_inh=INT_MAX; max_inh=INT_MIN;
00075   for(j=0;j<N*N;j++)
00076   {
00077     fscanf(finh,"%le ",&w);
00078     if(w<min_inh)
00079       min_inh = w;
00080     if(w>max_inh)
00081       max_inh = w;
00082   }
00083   fclose(finh);
00084 
00085   N3=ceil((NFFT_MAX(fabs(min_inh),fabs(max_inh))*(max_time-min_time)/2.0+(m)/(2*sigma))*4*sigma);
00086   /* N3 has to be even */
00087   if(N3%2!=0)
00088     N3++;
00089 
00090   T=((max_time-min_time)/2.0)/(0.5-((double) (m))/N3);
00091   W=N3/T;
00092 
00093   my_N[0]=N; my_n[0]=ceil(N*sigma);
00094   my_N[1]=N; my_n[1]=ceil(N*sigma);
00095   my_N[2]=N3; my_n[2]=N3;
00096 
00097   /* initialise nfft */
00098   mri_inh_2d1d_init_guru(&my_plan, my_N, M, my_n, m, sigma, flags,
00099                       FFTW_MEASURE| FFTW_DESTROY_INPUT);
00100 
00101 
00102   /* precompute lin psi if set */
00103   if(my_plan.plan.nfft_flags & PRE_LIN_PSI)
00104     nfft_precompute_lin_psi(&my_plan.plan);
00105 
00106   if (weight)
00107     infft_flags = infft_flags | PRECOMPUTE_WEIGHT;
00108 
00109   /* initialise my_iplan, advanced */
00110   solver_init_advanced_complex(&my_iplan,(mv_plan_complex*)(&my_plan), infft_flags );
00111 
00112   /* get the weights */
00113   if(my_iplan.flags & PRECOMPUTE_WEIGHT)
00114   {
00115     fw=fopen("weights.dat","r");
00116     for(j=0;j<my_plan.M_total;j++)
00117     {
00118         fscanf(fw,"%le ",&my_iplan.w[j]);
00119     }
00120     fclose(fw);
00121   }
00122 
00123   /* get the damping factors */
00124   if(my_iplan.flags & PRECOMPUTE_DAMP)
00125   {
00126     for(j=0;j<N;j++){
00127       for(k=0;k<N;k++) {
00128         int j2= j-N/2;
00129         int k2= k-N/2;
00130         double r=sqrt(j2*j2+k2*k2);
00131         if(r>(double) N/2)
00132           my_iplan.w_hat[j*N+k]=0.0;
00133         else
00134           my_iplan.w_hat[j*N+k]=1.0;
00135       }
00136     }
00137   }
00138 
00139   fp=fopen(filename,"r");
00140   ftime=fopen("readout_time.dat","r");
00141 
00142   for(j=0;j<my_plan.M_total;j++)
00143   {
00144     fscanf(fp,"%le %le %le %le",&my_plan.plan.x[2*j+0],&my_plan.plan.x[2*j+1],&real,&imag);
00145     my_iplan.y[j]=real+ _Complex_I*imag;
00146     fscanf(ftime,"%le ",&my_plan.t[j]);
00147 
00148     my_plan.t[j] = (my_plan.t[j]-Ts)/T;
00149   }
00150   fclose(fp);
00151   fclose(ftime);
00152 
00153 
00154   finh=fopen("inh.dat","r");
00155   for(j=0;j<N*N;j++)
00156   {
00157     fscanf(finh,"%le ",&my_plan.w[j]);
00158     my_plan.w[j]/=W;
00159   }
00160   fclose(finh);
00161 
00162 
00163   if(my_plan.plan.nfft_flags & PRE_PSI) {
00164     nfft_precompute_psi(&my_plan.plan);
00165   }
00166   if(my_plan.plan.nfft_flags & PRE_FULL_PSI) {
00167       nfft_precompute_full_psi(&my_plan.plan);
00168   }
00169 
00170   /* init some guess */
00171   for(j=0;j<my_plan.N_total;j++)
00172   {
00173     my_iplan.f_hat_iter[j]=0.0;
00174   }
00175 
00176   t=nfft_second();
00177 
00178   /* inverse trafo */
00179   solver_before_loop_complex(&my_iplan);
00180   for(l=0;l<iteration;l++)
00181   {
00182     /* break if dot_r_iter is smaller than epsilon*/
00183     if(my_iplan.dot_r_iter<epsilon)
00184     break;
00185     fprintf(stderr,"%e,  %i of %i\n",sqrt(my_iplan.dot_r_iter),
00186     l+1,iteration);
00187     solver_loop_one_step_complex(&my_iplan);
00188   }
00189 
00190   t=nfft_second()-t;
00191 #ifdef HAVE_MALLINFO
00192   fprintf(stderr,"time: %e seconds mem: %i \n",t,nfft_total_used_memory());
00193 #else
00194   fprintf(stderr,"time: %e seconds mem: mallinfo not available\n",t);
00195 #endif
00196 
00197   fout_real=fopen("output_real.dat","w");
00198   fout_imag=fopen("output_imag.dat","w");
00199 
00200   for (j=0;j<N*N;j++) {
00201     /* Verschiebung wieder herausrechnen */
00202     my_iplan.f_hat_iter[j]*=cexp(-2.0*_Complex_I*PI*Ts*my_plan.w[j]*W);
00203 
00204     fprintf(fout_real,"%le ",creal(my_iplan.f_hat_iter[j]));
00205     fprintf(fout_imag,"%le ",cimag(my_iplan.f_hat_iter[j]));
00206   }
00207 
00208   fclose(fout_real);
00209   fclose(fout_imag);
00210   solver_finalize_complex(&my_iplan);
00211   mri_inh_2d1d_finalize(&my_plan);
00212 }
00213 
00214 
00215 int main(int argc, char **argv)
00216 {
00217   if (argc <= 5) {
00218 
00219     printf("usage: ./reconstruct_data_inh_2d1d FILENAME N M ITER WEIGHTS\n");
00220     return 1;
00221   }
00222 
00223   reconstruct(argv[1],atoi(argv[2]),atoi(argv[3]),atoi(argv[4]),atoi(argv[5]));
00224 
00225   return 1;
00226 }
00227 /* \} */

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