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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 3328 2009-09-14 12:01:12Z 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_nfft_1d(void)
00031 {
00032   nfft_plan p;
00033   double t;
00034 
00035   int N=20000;
00036   int M=20000;
00037   int n=32;
00038 
00040   nfft_init_1d(&p,N,M);
00041 
00043   nfft_vrand_shifted_unit_double(p.x,p.M_total);
00044  
00046   if(p.nfft_flags & PRE_ONE_PSI)
00047       nfft_precompute_one_psi(&p);
00048 
00050   nfft_vrand_unit_complex(p.f_hat,p.N_total);
00051 //  nfft_vpr_complex(p.f_hat,p.N_total,"given Fourier coefficients, vector f_hat");
00052 
00054   t=nfft_second();
00055   ndft_trafo(&p);
00056   t=nfft_second()-t;
00057 //  nfft_vpr_complex(p.f,p.M_total,"ndft, vector f");
00058   printf(" took %e seconds.\n",t);
00059 
00060 //  /** approx. trafo and show the result */
00061 //  nfft_trafo(&p);
00062 //  nfft_vpr_complex(p.f,p.M_total,"nfft, vector f");
00063 //
00064 //  /** approx. adjoint and show the result */
00065 //  ndft_adjoint(&p);
00066 //  nfft_vpr_complex(p.f_hat,p.N_total,"adjoint ndft, vector f_hat");
00067 //
00068 //  /** approx. adjoint and show the result */
00069 //  nfft_adjoint(&p);
00070 //  nfft_vpr_complex(p.f_hat,p.N_total,"adjoint nfft, vector f_hat");
00071 
00073   nfft_finalize(&p);
00074 }
00075 
00076 void simple_test_nfft_2d(void)
00077 {
00078   int K,N[2],n[2],k,M;
00079   double t;
00080 
00081   nfft_plan p;
00082 
00083   N[0]=32; n[0]=64;
00084   N[1]=14; n[1]=32;
00085   M=N[0]*N[1];
00086   K=16;
00087 
00088   t=nfft_second();
00090   nfft_init_guru(&p, 2, N, M, n, 7,
00091      PRE_PHI_HUT| PRE_FULL_PSI| MALLOC_F_HAT| MALLOC_X| MALLOC_F |
00092      FFTW_INIT| FFT_OUT_OF_PLACE,
00093      FFTW_ESTIMATE| FFTW_DESTROY_INPUT);
00094 
00096   nfft_vrand_shifted_unit_double(p.x,p.d*p.M_total);
00097 
00099   if(p.nfft_flags & PRE_ONE_PSI)
00100     nfft_precompute_one_psi(&p);
00101 
00103   nfft_vrand_unit_complex(p.f_hat,p.N_total);
00104 
00105   t=nfft_second()-t;
00106   nfft_vpr_complex(p.f_hat,K,
00107               "given Fourier coefficients, vector f_hat (first few entries)");
00108   printf(" ... initialisation took %e seconds.\n",t);
00109 
00111   t=nfft_second();
00112   ndft_trafo(&p);
00113   t=nfft_second()-t;
00114   nfft_vpr_complex(p.f,K,"ndft, vector f (first few entries)");
00115   printf(" took %e seconds.\n",t);
00116 
00118   t=nfft_second();
00119   nfft_trafo(&p);
00120   t=nfft_second()-t;
00121   nfft_vpr_complex(p.f,K,"nfft, vector f (first few entries)");
00122   printf(" took %e seconds.\n",t);
00123 
00125   t=nfft_second();
00126   ndft_adjoint(&p);
00127   t=nfft_second()-t;
00128   nfft_vpr_complex(p.f_hat,K,"adjoint ndft, vector f_hat (first few entries)");
00129   printf(" took %e seconds.\n",t);
00130 
00132   t=nfft_second();
00133   nfft_adjoint(&p);
00134   t=nfft_second()-t;
00135   nfft_vpr_complex(p.f_hat,K,"adjoint nfft, vector f_hat (first few entries)");
00136   printf(" took %e seconds.\n",t);
00137 
00139   nfft_finalize(&p);
00140 }
00141 
00142 int main(void)
00143 {
00144   system("clear");
00145   printf("1) computing an one dimensional ndft, nfft and an adjoint nfft\n\n");
00146   simple_test_nfft_1d();
00147 //  getc(stdin);
00148 //
00149 //  system("clear");
00150 //  printf("2) computing a two dimensional ndft, nfft and an adjoint nfft\n\n");
00151 //  simple_test_nfft_2d();
00152 
00153   return 1;
00154 }

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