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glacier.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: glacier.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 
00038 double my_weight(double z,double a,double b,double c)
00039 {
00040     return pow(0.25-z*z,b)/(c+pow(fabs(z),2*a));
00041 }
00042 
00044 void glacier(int N,int M)
00045 {
00046   int j,k,k0,k1,l,my_N[2],my_n[2];
00047   double tmp_y;
00048   nfft_plan p;
00049   solver_plan_complex ip;
00050   FILE* fp;
00051 
00052   /* initialise p */
00053   my_N[0]=N; my_n[0]=nfft_next_power_of_2(N);
00054   my_N[1]=N; my_n[1]=nfft_next_power_of_2(N);
00055   nfft_init_guru(&p, 2, my_N, M, my_n, 6,
00056      PRE_PHI_HUT| PRE_FULL_PSI|
00057      MALLOC_X| MALLOC_F_HAT| MALLOC_F|
00058      FFTW_INIT| FFT_OUT_OF_PLACE,
00059      FFTW_MEASURE| FFTW_DESTROY_INPUT);
00060 
00061   /* initialise ip, specific */
00062   solver_init_advanced_complex(&ip,(mv_plan_complex*)(&p), CGNE| PRECOMPUTE_DAMP);
00063   fprintf(stderr,"Using the generic solver!");
00064 
00065   /* init nodes */
00066   fp=fopen("input_data.dat","r");
00067   for(j=0;j<p.M_total;j++)
00068   {
00069       fscanf(fp,"%le %le %le",&p.x[2*j+0],&p.x[2*j+1],&tmp_y);
00070       ip.y[j]=tmp_y;
00071   }
00072   fclose(fp);
00073 
00074   /* precompute psi */
00075   if(p.nfft_flags & PRE_ONE_PSI)
00076       nfft_precompute_one_psi(&p);
00077 
00078   /* initialise damping factors */
00079   if(ip.flags & PRECOMPUTE_DAMP)
00080     for(k0=0;k0<p.N[0];k0++)
00081       for(k1=0;k1<p.N[1];k1++)
00082         ip.w_hat[k0*p.N[1]+k1]=
00083       my_weight(((double)(k0-p.N[0]/2))/p.N[0],0.5,3,0.001)*
00084       my_weight(((double)(k1-p.N[1]/2))/p.N[1],0.5,3,0.001);
00085 
00086   /* init some guess */
00087   for(k=0;k<p.N_total;k++)
00088       ip.f_hat_iter[k]=0;
00089 
00090   /* inverse trafo */
00091   solver_before_loop_complex(&ip);
00092   for(l=0;l<40;l++)
00093     {
00094       fprintf(stderr,"Residual ||r||=%e,\n",sqrt(ip.dot_r_iter));
00095       solver_loop_one_step_complex(&ip);
00096     }
00097 
00098   for(k=0;k<p.N_total;k++)
00099     printf("%le %le\n",creal(ip.f_hat_iter[k]),cimag(ip.f_hat_iter[k]));
00100 
00101   solver_finalize_complex(&ip);
00102   nfft_finalize(&p);
00103 }
00104 
00106 void glacier_cv(int N,int M,int M_cv,unsigned solver_flags)
00107 {
00108   int j,k,k0,k1,l,my_N[2],my_n[2];
00109   double tmp_y,r;
00110   nfft_plan p,cp;
00111   solver_plan_complex ip;
00112   double _Complex* cp_y;
00113   FILE* fp;
00114   int M_re=M-M_cv;
00115 
00116   /* initialise p for reconstruction */
00117   my_N[0]=N; my_n[0]=nfft_next_power_of_2(N);
00118   my_N[1]=N; my_n[1]=nfft_next_power_of_2(N);
00119   nfft_init_guru(&p, 2, my_N, M_re, my_n, 6,
00120      PRE_PHI_HUT| PRE_FULL_PSI|
00121      MALLOC_X| MALLOC_F_HAT| MALLOC_F|
00122      FFTW_INIT| FFT_OUT_OF_PLACE,
00123      FFTW_MEASURE| FFTW_DESTROY_INPUT);
00124 
00125 
00126   /* initialise ip, specific */
00127   solver_init_advanced_complex(&ip,(mv_plan_complex*)(&p), solver_flags);
00128 
00129   /* initialise cp for validation */
00130   cp_y = (double _Complex*) nfft_malloc(M*sizeof(double _Complex));
00131   nfft_init_guru(&cp, 2, my_N, M, my_n, 6,
00132      PRE_PHI_HUT| PRE_FULL_PSI|
00133      MALLOC_X| MALLOC_F|
00134      FFTW_INIT| FFT_OUT_OF_PLACE,
00135      FFTW_MEASURE| FFTW_DESTROY_INPUT);
00136 
00137   cp.f_hat=ip.f_hat_iter;
00138 
00139   /* set up data in cp and cp_y */
00140   fp=fopen("input_data.dat","r");
00141   for(j=0;j<cp.M_total;j++)
00142     {
00143       fscanf(fp,"%le %le %le",&cp.x[2*j+0],&cp.x[2*j+1],&tmp_y);
00144       cp_y[j]=tmp_y;
00145     }
00146   fclose(fp);
00147 
00148   /* copy part of the data to p and ip */
00149   for(j=0;j<p.M_total;j++)
00150   {
00151       p.x[2*j+0]=cp.x[2*j+0];
00152       p.x[2*j+1]=cp.x[2*j+1];
00153       ip.y[j]=tmp_y;
00154   }
00155 
00156   /* precompute psi */
00157   if(p.nfft_flags & PRE_ONE_PSI)
00158     nfft_precompute_one_psi(&p);
00159 
00160   /* precompute psi */
00161   if(cp.nfft_flags & PRE_ONE_PSI)
00162     nfft_precompute_one_psi(&cp);
00163 
00164   /* initialise damping factors */
00165   if(ip.flags & PRECOMPUTE_DAMP)
00166     for(k0=0;k0<p.N[0];k0++)
00167       for(k1=0;k1<p.N[1];k1++)
00168         ip.w_hat[k0*p.N[1]+k1]=
00169       my_weight(((double)(k0-p.N[0]/2))/p.N[0],0.5,3,0.001)*
00170       my_weight(((double)(k1-p.N[1]/2))/p.N[1],0.5,3,0.001);
00171 
00172   /* init some guess */
00173   for(k=0;k<p.N_total;k++)
00174       ip.f_hat_iter[k]=0;
00175 
00176   /* inverse trafo */
00177   solver_before_loop_complex(&ip);
00178   //  fprintf(stderr,"iteration starts,\t");
00179   for(l=0;l<40;l++)
00180     solver_loop_one_step_complex(&ip);
00181 
00182   //fprintf(stderr,"r=%1.2e, ",sqrt(ip.dot_r_iter)/M_re);
00183 
00184   NFFT_SWAP_complex(p.f_hat,ip.f_hat_iter);
00185   nfft_trafo(&p);
00186   NFFT_SWAP_complex(p.f_hat,ip.f_hat_iter);
00187   nfft_upd_axpy_complex(p.f,-1,ip.y,M_re);
00188   r=sqrt(nfft_dot_complex(p.f,M_re)/nfft_dot_complex(cp_y,M));
00189   fprintf(stderr,"r=%1.2e, ",r);
00190   printf("$%1.1e$ & ",r);
00191 
00192   nfft_trafo(&cp);
00193   nfft_upd_axpy_complex(&cp.f[M_re],-1,&cp_y[M_re],M_cv);
00194   r=sqrt(nfft_dot_complex(&cp.f[M_re],M_cv)/nfft_dot_complex(cp_y,M));
00195   fprintf(stderr,"r_1=%1.2e\t",r);
00196   printf("$%1.1e$ & ",r);
00197 
00198   nfft_finalize(&cp);
00199   solver_finalize_complex(&ip);
00200   nfft_finalize(&p);
00201 }
00202 
00203 
00205 int main(int argc, char **argv)
00206 {
00207   int M_cv;
00208 
00209   if(argc<3)
00210     {
00211       fprintf(stderr,"Call this program from the Matlab script glacier.m!");
00212       exit(-1);
00213     }
00214 
00215   if(argc==3)
00216     glacier(atoi(argv[1]),atoi(argv[2]));
00217   else
00218     for(M_cv=atoi(argv[3]);M_cv<=atoi(argv[5]);M_cv+=atoi(argv[4]))
00219       {
00220   fprintf(stderr,"\nM_cv=%d,\t",M_cv);
00221   printf("$%d$ & ",M_cv);
00222   fprintf(stderr,"cgne+damp: ");
00223   glacier_cv(atoi(argv[1]),atoi(argv[2]),M_cv,CGNE| PRECOMPUTE_DAMP);
00224   //fprintf(stderr,"cgne: ");
00225   //glacier_cv(atoi(argv[1]),atoi(argv[2]),M_cv,CGNE);
00226   fprintf(stderr,"cgnr: ");
00227   glacier_cv(atoi(argv[1]),atoi(argv[2]),M_cv,CGNR);
00228   fprintf(stderr,"cgnr: ");
00229   glacier_cv(atoi(argv[1])/4,atoi(argv[2]),M_cv,CGNR);
00230   printf("XXX \\\\\n");
00231       }
00232 
00233   fprintf(stderr,"\n");
00234 
00235   return 1;
00236 }
00237 /* \} */

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