NFFT: nfft_plan Struct Reference

NFFT 3.4.1

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

#include <nfft3.h>

Public Member Functions
	FFTW_MANGLE_DOUBLE (plan) my_fftw_plan1
	Forward FFTW plan.

	FFTW_MANGLE_DOUBLE (plan) my_fftw_plan2
	Backward FFTW plan.

Data Fields
NFFT_INT	N_total
	Total number of Fourier coefficients. More...

NFFT_INT	M_total
	Total number of samples. More...

fftw_complex *	f_hat
	Fourier coefficients. More...

fftw_complex *	f
	Samples. More...

void(*	mv_trafo )(void *)
	Transform. More...

void(*	mv_adjoint )(void *)
	Adjoint transform. More...

NFFT_INT	d
	Dimension (rank). More...

NFFT_INT *	N
	Multi-bandwidth. More...

double *	sigma
	Oversampling factor. More...

NFFT_INT *	n
	Length of FFTW transforms. More...

NFFT_INT	n_total
	Combined total length of FFTW transforms. More...

NFFT_INT	m
	Cut-off parameter for window function. More...

double *	b
	Shape parameter for window function.

NFFT_INT	K
	Number of equispaced samples of window function. More...

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.

double *	x
	Nodes in time/spatial domain, size is doubles.

double	MEASURE_TIME_t [3]
	Measured time for each step if MEASURE_TIME is set.

double **	c_phi_inv
	Precomputed data for the diagonal matrix , size \ is $N_0+\dots+N_{d-1}$ doubles.

double *	psi
	Precomputed data for the sparse matrix , 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.

fftw_complex *	g
	Oversampled vector of samples, size is n_total double complex.

fftw_complex *	g_hat
	Zero-padded vector of Fourier coefficients, size is n_total fftw_complex.

fftw_complex *	g1
	Input of fftw.

fftw_complex *	g2
	Output of fftw.

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. More...

Detailed Description

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

NFFT transform plan

Definition at line 192 of file nfft3.h.

Field Documentation

NFFT_INT nfft_plan::N_total

Total number of Fourier coefficients.

Definition at line 192 of file nfft3.h.

Referenced by mri_inh_2d1d_init_guru(), nfsoft_trafo(), nsfft_cp(), and reconstruct().

NFFT_INT nfft_plan::M_total

Total number of samples.

Definition at line 192 of file nfft3.h.

Referenced by construct(), mri_inh_2d1d_init_guru(), nfsoft_precompute(), and reconstruct().

fftw_complex* nfft_plan::f_hat

Fourier coefficients.

Definition at line 192 of file nfft3.h.

Referenced by construct(), mri_inh_2d1d_finalize(), mri_inh_2d1d_init_guru(), mri_inh_2d1d_trafo(), mri_inh_3d_adjoint(), mri_inh_3d_trafo(), nfsft_adjoint(), nfsft_trafo(), nfsoft_adjoint(), nfsoft_trafo(), nsfft_cp(), and reconstruct().

fftw_complex* nfft_plan::f

Samples.

Definition at line 192 of file nfft3.h.

Referenced by construct(), mri_inh_2d1d_finalize(), mri_inh_2d1d_init_guru(), mri_inh_2d1d_trafo(), mri_inh_3d_adjoint(), mri_inh_3d_trafo(), nfsft_adjoint(), nfsft_trafo(), nfsoft_adjoint(), nfsoft_trafo(), nnfft_adjoint(), nnfft_trafo(), and reconstruct().

void(* nfft_plan::mv_trafo)(void *)

Transform.

Definition at line 192 of file nfft3.h.

void(* nfft_plan::mv_adjoint)(void *)

Adjoint transform.

Definition at line 192 of file nfft3.h.

NFFT_INT nfft_plan::d

Dimension (rank).

Definition at line 192 of file nfft3.h.

NFFT_INT* nfft_plan::N

Multi-bandwidth.

Definition at line 192 of file nfft3.h.

double* nfft_plan::sigma

Oversampling factor.

Definition at line 192 of file nfft3.h.

NFFT_INT* nfft_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 192 of file nfft3.h.

NFFT_INT nfft_plan::n_total

Combined total length of FFTW transforms.

Definition at line 192 of file nfft3.h.

NFFT_INT nfft_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 192 of file nfft3.h.

Referenced by mri_inh_2d1d_trafo(), mri_inh_3d_adjoint(), and mri_inh_3d_trafo().

NFFT_INT nfft_plan::K

Number of equispaced samples of window function.

Used for flag PRE_LIN_PSI.

Definition at line 192 of file nfft3.h.

NFFT_INT* nfft_plan::index_x

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

Definition at line 192 of file nfft3.h.

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

nfft3.h