static void simple_test_nnfft_2d(void)
{
int j,k; /**< index for nodes and freqencies */
nnfft_plan my_plan; /**< plan for the nfft */
int N[2];
N[0]=12;
N[1]=14;
/** init an one dimensional plan */
nnfft_init(&my_plan, 2,12*14,19, N);
/** init pseudo random nodes */
for(j=0;j<my_plan.M_total;j++)
{
my_plan.x[2*j]=((double)rand())/((double)RAND_MAX)-0.5;
my_plan.x[2*j+1]=((double)rand())/((double)RAND_MAX)-0.5;
}
/** init pseudo random nodes */
for(j=0;j<my_plan.N_total;j++)
{
my_plan.v[2*j]=((double)rand())/((double)RAND_MAX)-0.5;
my_plan.v[2*j+1]=((double)rand())/((double)RAND_MAX)-0.5;
}
/** precompute psi, the entries of the matrix B */
if(my_plan.nnfft_flags & PRE_PSI)
nnfft_precompute_psi(&my_plan);
if(my_plan.nnfft_flags & PRE_FULL_PSI)
nnfft_precompute_full_psi(&my_plan);
if(my_plan.nnfft_flags & PRE_LIN_PSI)
nnfft_precompute_lin_psi(&my_plan);
/** precompute phi_hut, the entries of the matrix D */
if(my_plan.nnfft_flags & PRE_PHI_HUT)
nnfft_precompute_phi_hut(&my_plan);
/** init pseudo random Fourier coefficients and show them */
for(k=0;k<my_plan.N_total;k++)
my_plan.f_hat[k] = ((double)rand())/((double)RAND_MAX) + _Complex_I*((double)rand())/((double)RAND_MAX);
nfft_vpr_complex(my_plan.f_hat,12,
"given Fourier coefficients, vector f_hat (first 12 entries)");
/** direct trafo and show the result */
nnfft_trafo_direct(&my_plan);
nfft_vpr_complex(my_plan.f,my_plan.M_total,"ndft, vector f");
/** approx. trafo and show the result */
nnfft_trafo(&my_plan);
nfft_vpr_complex(my_plan.f,my_plan.M_total,"nfft, vector f");
/** finalise the one dimensional plan */
nnfft_finalize(&my_plan);
}
static void measure_time_nnfft_1d(void)
{
int j,k; /**< index for nodes and freqencies */
nnfft_plan my_plan; /**< plan for the nfft */
int my_N,N=4;
double t;
double t0, t1;
for(my_N=16; my_N<=16384; my_N*=2)
{
nnfft_init(&my_plan,1,my_N,my_N,&N);
for(j=0;j<my_plan.M_total;j++)
my_plan.x[j]=((double)rand())/((double)RAND_MAX)-0.5;
for(j=0;j<my_plan.N_total;j++)
my_plan.v[j]=((double)rand())/((double)RAND_MAX)-0.5;
if(my_plan.nnfft_flags & PRE_PSI)
nnfft_precompute_psi(&my_plan);
if(my_plan.nnfft_flags & PRE_FULL_PSI)
nnfft_precompute_full_psi(&my_plan);
if(my_plan.nnfft_flags & PRE_PHI_HUT)
nnfft_precompute_phi_hut(&my_plan);
for(k=0;k<my_plan.N_total;k++)
my_plan.f_hat[k] = ((double)rand())/((double)RAND_MAX) + _Complex_I*((double)rand())/((double)RAND_MAX);
t0 = nfft_clock_gettime_seconds();
nnfft_trafo_direct(&my_plan);
t1 = nfft_clock_gettime_seconds();
t = t1 - t0;
printf("t_nndft=%e,\t",t);
t0 = nfft_clock_gettime_seconds();
nnfft_trafo(&my_plan);
t1 = nfft_clock_gettime_seconds();
t = t1 - t0;
printf("t_nnfft=%e\t",t);
printf("(N=M=%d)\n",my_N);
nnfft_finalize(&my_plan);
}
}
void accuracy(int d)
{
int m,t;
nnfft_plan my_plan;
double complex *slow;
int N[d],n[d];
int M_total,N_total;
M_total=10000;N_total=1;
slow=(double complex*)fftw_malloc(M_total*sizeof(double complex));
for(t=0; t<d; t++)
{
N[t]=(1<<(12/d));
n[t]=2*N[t];
N_total*=N[t];
}
/** init a plan */
for(m=0; m<10; m++)
{
nnfft_init_guru(&my_plan, d, N_total, M_total, N, n, m,
PRE_PSI| PRE_PHI_HUT|
MALLOC_X| MALLOC_V| MALLOC_F_HAT| MALLOC_F);
/** init pseudo random nodes */
nfft_vrand_shifted_unit_double(my_plan.x, d*my_plan.M_total);
nfft_vrand_shifted_unit_double(my_plan.v, d*my_plan.N_total);
/** precompute psi, the entries of the matrix B */
if(my_plan.nnfft_flags & PRE_PSI)
nnfft_precompute_psi(&my_plan);
if(my_plan.nnfft_flags & PRE_LIN_PSI)
nnfft_precompute_lin_psi(&my_plan);
if(my_plan.nnfft_flags & PRE_FULL_PSI)
nnfft_precompute_full_psi(&my_plan);
/** precompute psi, the entries of the matrix D */
if(my_plan.nnfft_flags & PRE_PHI_HUT)
nnfft_precompute_phi_hut(&my_plan);
/** init pseudo random Fourier coefficients */
nfft_vrand_unit_complex(my_plan.f_hat, my_plan.N_total);
/** direct trafo and show the result */
nndft_trafo(&my_plan);
NFFT_SWAP_complex(my_plan.f,slow);
/** approx. trafo and show the result */
nnfft_trafo(&my_plan);
printf("%e, %e\n",
nfft_error_l_infty_complex(slow, my_plan.f, M_total),
nfft_error_l_infty_1_complex(slow, my_plan.f, M_total, my_plan.f_hat,
my_plan.N_total));
/** finalise the one dimensional plan */
nnfft_finalize(&my_plan);
}
}
static void simple_test_innfft_1d(void)
{
int j,k,l,N=8; /**< index for nodes, freqencies, iter*/
nnfft_plan my_plan; /**< plan for the nnfft */
solver_plan_complex my_iplan; /**< plan for the inverse nnfft */
/** initialise an one dimensional plan */
nnfft_init(&my_plan,1 ,8 ,8 ,&N);
/** initialise my_iplan */
solver_init_advanced_complex(&my_iplan,(nfft_mv_plan_complex*)(&my_plan),CGNR);
/** init pseudo random nodes */
for(j=0;j<my_plan.M_total;j++)
my_plan.x[j]=((double)rand())/((double)RAND_MAX)-0.5;
/** init pseudo random nodes */
for(k=0;k<my_plan.N_total;k++)
my_plan.v[k]=((double)rand())/((double)RAND_MAX)-0.5;
/** precompute psi, the entries of the matrix B */
if(my_plan.nnfft_flags & PRE_PSI)
nnfft_precompute_psi(&my_plan);
if(my_plan.nnfft_flags & PRE_FULL_PSI)
nnfft_precompute_full_psi(&my_plan);
/** precompute phi_hut, the entries of the matrix D */
if(my_plan.nnfft_flags & PRE_PHI_HUT)
nnfft_precompute_phi_hut(&my_plan);
/** init pseudo random samples (real) and show them */
for(j=0;j<my_plan.M_total;j++)
my_iplan.y[j] = ((double)rand())/((double)RAND_MAX);
nfft_vpr_complex(my_iplan.y,my_plan.M_total,"given data, vector given_f");
/** initialise some guess f_hat_0 */
for(k=0;k<my_plan.N_total;k++)
my_iplan.f_hat_iter[k] = 0.0;
nfft_vpr_complex(my_iplan.f_hat_iter,my_plan.N_total,
"approximate solution, vector f_hat_iter");
/** solve the system */
solver_before_loop_complex(&my_iplan);
for(l=0;l<8;l++)
{
printf("iteration l=%d\n",l);
solver_loop_one_step_complex(&my_iplan);
nfft_vpr_complex(my_iplan.f_hat_iter,my_plan.N_total,
"approximate solution, vector f_hat_iter");
CSWAP(my_iplan.f_hat_iter,my_plan.f_hat);
nnfft_trafo(&my_plan);
nfft_vpr_complex(my_plan.f,my_plan.M_total,"fitting the data, vector f");
CSWAP(my_iplan.f_hat_iter,my_plan.f_hat);
}
solver_finalize_complex(&my_iplan);
nnfft_finalize(&my_plan);
}
