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simple_test.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: simple_test.c 3198 2009-05-27 14:16:50Z keiner $ */
00020 
00021 #include <stdio.h>
00022 #include <math.h>
00023 #include <string.h>
00024 #include <stdlib.h>
00025 #include <complex.h>
00026 
00027 #include "nfft3util.h"
00028 #include "nfft3.h"
00029 
00030 /* void simple_test_infft_1d(int N, int M, int iter) */
00031 /* { */
00032 /*   int k,l;                            /\**< index for nodes, freqencies,iter*\/ */
00033 /*   nfft_plan p;                          /\**< plan for the nfft               *\/ */
00034 /*   infft_plan ip;                        /\**< plan for the inverse nfft       *\/ */
00035 
00036 /*   /\** initialise an one dimensional plan *\/ */
00037 /*   nfft_init_1d(&p, N, M); */
00038 
00039 /*   /\** init pseudo random nodes *\/ */
00040 /*   nfft_vrand_shifted_unit_double(p.x,p.M_total); */
00041 
00042 /*   /\** precompute psi, the entries of the matrix B *\/ */
00043 /*   if(p.nfft_flags & PRE_ONE_PSI) */
00044 /*     nfft_precompute_one_psi(&p); */
00045 
00046 /*   /\** initialise inverse plan *\/ */
00047 /*   infft_init(&ip,&p); */
00048 
00049 /*   /\** init pseudo random samples and show them *\/ */
00050 /*   nfft_vrand_unit_complex(ip.y,p.M_total); */
00051 /*   nfft_vpr_complex(ip.y,p.M_total,"Given data, vector y"); */
00052 
00053 /*   /\** initialise some guess f_hat_0 and solve *\/ */
00054 /*   for(k=0;k<p.N_total;k++) */
00055 /*       ip.f_hat_iter[k]=0; */
00056 
00057 /*   nfft_vpr_complex(ip.f_hat_iter,p.N_total,"Initial guess, vector f_hat_iter"); */
00058 
00059 /*   NFFT_SWAP_complex(ip.f_hat_iter,p.f_hat); */
00060 /*   nfft_trafo(&p); */
00061 /*   nfft_vpr_complex(p.f,p.M_total,"Data fit, vector f"); */
00062 /*   NFFT_SWAP_complex(ip.f_hat_iter,p.f_hat); */
00063 
00064 /*   infft_before_loop(&ip); */
00065 /*   printf("\n Residual r=%e\n",ip.dot_r_iter); */
00066 
00067 /*   for(l=0;l<iter;l++) */
00068 /*     { */
00069 /*       printf("\n********** Iteration l=%d **********\n",l); */
00070 /*       infft_loop_one_step(&ip); */
00071 /*       nfft_vpr_complex(ip.f_hat_iter,p.N_total, */
00072 /*      "Approximate solution, vector f_hat_iter"); */
00073 
00074 /*       NFFT_SWAP_complex(ip.f_hat_iter,p.f_hat); */
00075 /*       nfft_trafo(&p); */
00076 /*       nfft_vpr_complex(p.f,p.M_total,"Data fit, vector f"); */
00077 /*       NFFT_SWAP_complex(ip.f_hat_iter,p.f_hat); */
00078 
00079 /*       printf("\n Residual r=%e\n",ip.dot_r_iter); */
00080 /*     } */
00081 
00082 /*   infft_finalize(&ip); */
00083 /*   nfft_finalize(&p); */
00084 /* } */
00085 
00087 void simple_test_solver_nfft_1d(int N, int M, int iter)
00088 {
00089   int k,l;                            
00090   nfft_plan p;                          
00091   solver_plan_complex ip;                        
00094   nfft_init_1d(&p, N, M);
00095 
00097   nfft_vrand_shifted_unit_double(p.x,p.M_total);
00098 
00100   if(p.nfft_flags & PRE_ONE_PSI)
00101     nfft_precompute_one_psi(&p);
00102 
00104   solver_init_complex(&ip,(mv_plan_complex*)(&p));
00105 
00107   nfft_vrand_unit_complex(ip.y,p.M_total);
00108   nfft_vpr_complex(ip.y,p.M_total,"Given data, vector y");
00109 
00111   for(k=0;k<p.N_total;k++)
00112       ip.f_hat_iter[k]=0;
00113 
00114   nfft_vpr_complex(ip.f_hat_iter,p.N_total,"Initial guess, vector f_hat_iter");
00115 
00116   NFFT_SWAP_complex(ip.f_hat_iter,p.f_hat);
00117   nfft_trafo(&p);
00118   nfft_vpr_complex(p.f,p.M_total,"Data fit, vector f");
00119   NFFT_SWAP_complex(ip.f_hat_iter,p.f_hat);
00120 
00121   solver_before_loop_complex(&ip);
00122   printf("\n Residual r=%e\n",ip.dot_r_iter);
00123 
00124   for(l=0;l<iter;l++)
00125     {
00126       printf("\n********** Iteration l=%d **********\n",l);
00127       solver_loop_one_step_complex(&ip);
00128       nfft_vpr_complex(ip.f_hat_iter,p.N_total,
00129       "Approximate solution, vector f_hat_iter");
00130 
00131       NFFT_SWAP_complex(ip.f_hat_iter,p.f_hat);
00132       nfft_trafo(&p);
00133       nfft_vpr_complex(p.f,p.M_total,"Data fit, vector f");
00134       NFFT_SWAP_complex(ip.f_hat_iter,p.f_hat);
00135 
00136       printf("\n Residual r=%e\n",ip.dot_r_iter);
00137     }
00138 
00139   solver_finalize_complex(&ip);
00140   nfft_finalize(&p);
00141 }
00142 
00144 int main(void)
00145 {
00146   printf("\n Computing a one dimensional inverse nfft\n");
00147 
00148   simple_test_solver_nfft_1d(8,4,5);
00149 
00150   return 1;
00151 }
00152 /* \} */

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