3.0 API Reference

nfsft.c File Reference

Implementation file for the NFSFT module. More...

#include <math.h>
#include <stdlib.h>
#include <string.h>
#include "nfft3.h"
#include "legendre.h"
#include "api.h"
#include "util.h"

Go to the source code of this file.

Defines

#define NFSFT_DEFAULT_NFFT_CUTOFF   6

The default NFFT cutoff parameter.

#define NFSFT_DEFAULT_THRESHOLD   1000

The default threshold for the FPT.

#define NFSFT_BREAK_EVEN   5

The break-even bandwidth $N \in \mathbb{N}_0$ .

Functions

void c2e (nfsft_plan *plan)

Converts coefficients $\left(b_k^n\right)_{k=0}^M$ with $M \in \mathbb{N}_0$ , $-M \le n \le M$ from a linear combination of Chebyshev polynomials
$f(\cos\vartheta) = \sum_{k=0}^{2\lfloor\frac{M}{2}\rfloor} a_k (\sin\vartheta)^{n\;\mathrm{mod}\;2} T_k(\cos\vartheta)$
to coefficients $\left(c_k^n\right)_{k=0}^M$ matching the representation by complex exponentials
$f(\cos\vartheta) = \sum_{k=-M}^{M} c_k \mathrm{e}^{\mathrm{i}k\vartheta}$
for each order $n=-M,\ldots,M$ .

void c2e_transposed (nfsft_plan *plan)

Transposed version of the function c2e.

void nfsft_init (nfsft_plan *plan, int N, int M)

Creates a transform plan.

void nfsft_init_advanced (nfsft_plan *plan, int N, int M, unsigned int nfsft_flags)

Creates a transform plan.

void nfsft_init_guru (nfsft_plan *plan, int N, int M, unsigned int nfsft_flags, int nfft_flags, int nfft_cutoff)

Creates a transform plan.

void nfsft_precompute (int N, double kappa, unsigned int nfsft_flags, unsigned int fpt_flags)

Performes precomputation up to the next power of two with respect to a given bandwidth $N \in \mathbb{N}_2$ .

void nfsft_forget ()

Forgets all precomputed data.

void nfsft_finalize (nfsft_plan *plan)

Destroys a plan.

void ndsft_trafo (nfsft_plan *plan)

Executes a direct NDSFT, i.e.

void ndsft_adjoint (nfsft_plan *plan)

Executes a direct adjoint NDSFT, i.e.

void nfsft_trafo (nfsft_plan *plan)

Executes a NFSFT, i.e.

void nfsft_adjoint (nfsft_plan *plan)

Executes an adjoint NFSFT, i.e.

void nfsft_precompute_x (nfsft_plan *plan)

Variables

static struct nfsft_wisdom wisdom = {false,0U}

The global wisdom structure for precomputed data.

Detailed Description

Implementation file for the NFSFT module.

Author:: Jens Keiner

Definition in file nfsft.c.

Generated on 1 Nov 2006 by Doxygen 1.4.4


Defines
#define	NFSFT_DEFAULT_NFFT_CUTOFF 6
	The default NFFT cutoff parameter.
#define	NFSFT_DEFAULT_THRESHOLD 1000
	The default threshold for the FPT.
#define	NFSFT_BREAK_EVEN 5
	The break-even bandwidth $N \in \mathbb{N}_0$ .
Functions
void	c2e (nfsft_plan *plan)
	Converts coefficients $\left(b_k^n\right)_{k=0}^M$ with $M \in \mathbb{N}_0$ , $-M \le n \le M$ from a linear combination of Chebyshev polynomials $f(\cos\vartheta) = \sum_{k=0}^{2\lfloor\frac{M}{2}\rfloor} a_k (\sin\vartheta)^{n\;\mathrm{mod}\;2} T_k(\cos\vartheta)$ to coefficients $\left(c_k^n\right)_{k=0}^M$ matching the representation by complex exponentials $f(\cos\vartheta) = \sum_{k=-M}^{M} c_k \mathrm{e}^{\mathrm{i}k\vartheta}$ for each order $n=-M,\ldots,M$ .
void	c2e_transposed (nfsft_plan *plan)
	Transposed version of the function c2e.
void	nfsft_init (nfsft_plan *plan, int N, int M)
	Creates a transform plan.
void	nfsft_init_advanced (nfsft_plan *plan, int N, int M, unsigned int nfsft_flags)
	Creates a transform plan.
void	nfsft_init_guru (nfsft_plan *plan, int N, int M, unsigned int nfsft_flags, int nfft_flags, int nfft_cutoff)
	Creates a transform plan.
void	nfsft_precompute (int N, double kappa, unsigned int nfsft_flags, unsigned int fpt_flags)
	Performes precomputation up to the next power of two with respect to a given bandwidth $N \in \mathbb{N}_2$ .
void	nfsft_forget ()
	Forgets all precomputed data.
void	nfsft_finalize (nfsft_plan *plan)
	Destroys a plan.
void	ndsft_trafo (nfsft_plan *plan)
	Executes a direct NDSFT, i.e.
void	ndsft_adjoint (nfsft_plan *plan)
	Executes a direct adjoint NDSFT, i.e.
void	nfsft_trafo (nfsft_plan *plan)
	Executes a NFSFT, i.e.
void	nfsft_adjoint (nfsft_plan *plan)
	Executes an adjoint NFSFT, i.e.
void	nfsft_precompute_x (nfsft_plan *plan)
Variables
static struct nfsft_wisdom	wisdom = {false,0U}
	The global wisdom structure for precomputed data.