NFFT  3.3.2
Public Member Functions | Data Fields
nfftl_plan Struct Reference

data structure for an NFFT (nonequispaced fast Fourier transform) plan with long double precision More...

#include <nfft3.h>

Public Member Functions

 FFTW_MANGLE_LONG_DOUBLE (plan) my_fftw_plan1
 Forward FFTW plan.
 FFTW_MANGLE_LONG_DOUBLE (plan) my_fftw_plan2
 Backward FFTW plan.

Data Fields

NFFT_INT N_total
 Total number of Fourier coefficients.
NFFT_INT M_total
 Total number of samples.
fftwl_complex * f_hat
 Fourier coefficients.
fftwl_complex * f
 Samples.
void(* mv_trafo )(void *)
 Transform.
void(* mv_adjoint )(void *)
 Adjoint transform.
NFFT_INT d
 Dimension (rank).
NFFT_INT * N
 Multi-bandwidth.
long double * sigma
 Oversampling factor.
NFFT_INT * n
 Length of FFTW transforms.
NFFT_INT n_total
 Combined total length of FFTW transforms.
NFFT_INT m
 Cut-off parameter for window function.
long double * b
 Shape parameter for window function.
NFFT_INT K
 Number of equispaced samples of window function.
unsigned flags
 Flags for precomputation, (de)allocation, and FFTW usage, default setting is PRE_PHI_HUT | PRE_PSI | MALLOC_X | MALLOC_F_HAT | MALLOC_F | FFTW_INIT | FFT_OUT_OF_PLACE.
unsigned fftw_flags
 Flags for the FFTW, default is FFTW_ESTIMATE | FFTW_DESTROY_INPUT.
long double * x
 Nodes in time/spatial domain, size is $dM$ long doubles.
long double MEASURE_TIME_t [3]
 Measured time for each step if MEASURE_TIME is set.
long double ** c_phi_inv
 Precomputed data for the diagonal matrix $D$, size \ is $N_0+\hdots+N_{d-1}$ doubles.
long double * psi
 Precomputed data for the sparse matrix $B$, size depends on precomputation scheme.
NFFT_INT * psi_index_g
 Indices in source/target vector for PRE_FULL_PSI.
NFFT_INT * psi_index_f
 Indices in source/target vector for PRE_FULL_PSI.
fftwl_complex * g
 Oversampled vector of samples, size is n_total double complex.
fftwl_complex * g_hat
 Zero-padded vector of Fourier coefficients, size is n_total fftw_complex.
fftwl_complex * g1
 Input of fftw.
fftwl_complex * g2
 Output of fftw.
long double * spline_coeffs
 Input for de Boor algorithm if B_SPLINE or SINC_POWER is defined.
NFFT_INT * index_x
 Index array for nodes x used when flag NFFT_SORT_NODES is set.

Detailed Description

data structure for an NFFT (nonequispaced fast Fourier transform) plan with long double precision

Definition at line 178 of file nfft3.h.


Field Documentation

Total number of Fourier coefficients.

Definition at line 178 of file nfft3.h.

Total number of samples.

Definition at line 178 of file nfft3.h.

fftwl_complex* nfftl_plan::f_hat

Fourier coefficients.

Definition at line 178 of file nfft3.h.

fftwl_complex* nfftl_plan::f

Samples.

Definition at line 178 of file nfft3.h.

void(* nfftl_plan::mv_trafo)(void *)

Transform.

Definition at line 178 of file nfft3.h.

void(* nfftl_plan::mv_adjoint)(void *)

Adjoint transform.

Definition at line 178 of file nfft3.h.

NFFT_INT nfftl_plan::d

Dimension (rank).

Definition at line 178 of file nfft3.h.

NFFT_INT* nfftl_plan::N

Multi-bandwidth.

Definition at line 178 of file nfft3.h.

long double* nfftl_plan::sigma

Oversampling factor.

Definition at line 178 of file nfft3.h.

NFFT_INT* nfftl_plan::n

Length of FFTW transforms.

This is equal to sigma*N. The default is to use a power of two that satifies $2\le\sigma<4$.

Definition at line 178 of file nfft3.h.

Combined total length of FFTW transforms.

Definition at line 178 of file nfft3.h.

NFFT_INT nfftl_plan::m

Cut-off parameter for window function.

Default values for the different window functions are - 6 (KAISER_BESSEL), - 9 (SINC_POWER), - 11 (B_SPLINE), - 12 (GAUSSIAN)

Definition at line 178 of file nfft3.h.

NFFT_INT nfftl_plan::K

Number of equispaced samples of window function.

Used for flag PRE_LIN_PSI.

Definition at line 178 of file nfft3.h.

Index array for nodes x used when flag NFFT_SORT_NODES is set.

Definition at line 178 of file nfft3.h.


The documentation for this struct was generated from the following file: