fft Module Reference

Public Member Functions
subroutine, public	fft_r2r (u, length, num, kind, rescale)
	Compute a number of 1D FFTs or DCTs. More...
real(dp) function, public	wavenumber (i, N, L, kind)
	Get the wavenumber of the ith mode. More...
subroutine, public	transpose_grid (grid, grid_t, shape_x, idx, idx_t, comm)
	Global (parallel) transform of grid data. More...

Public Attributes
integer, parameter, public	w_forward = FFTW_REDFT10
integer, parameter, public	w_backward = FFTW_REDFT01
integer, parameter, public	p_forward = FFTW_R2HC
integer, parameter, public	p_backward = FFTW_HC2R

Private Attributes
integer, parameter	nplans = 10
integer	n_r2r_plans = 0
type(c_ptr), dimension(nplans)	r2r_plans
integer, dimension(nplans)	r2r_plan_lengths
integer, dimension(nplans)	r2r_plan_nums
integer(c_int), dimension(nplans)	r2r_plan_kinds

Detailed Description

Definition at line 12 of file fft_fftw_mod.F90.

Member Function/Subroutine Documentation

subroutine, public fft::fft_r2r	(	real(dp), dimension(:,:,:), intent(inout)	u,
		integer, intent(in)	length,
		integer, intent(in)	num,
		integer(c_int)	kind,
		real(dp), intent(inout)	rescale
	)

Compute a number of 1D FFTs or DCTs.

The transforms are performed inplace. Rescale is rescaled by the normalization factor of the transform.

Parameters

[in,out]	u	data, leading dim is transformed
[in]	length	length of leading dimension
[in]	num	number of transforms
	kind	Type of transform. See pulic parameters
[in,out]	rescale	Normalization factor

Definition at line 41 of file fft_fftw_mod.F90.

Referenced by poisson::cos_test(), poisson::shuffle_test(), and poisson::spectral_solve().

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subroutine, public fft::transpose_grid	(	real(dp), dimension(0:,0:,0:), intent(inout)	grid,
		real(dp), dimension(0:,0:,0:), intent(out)	grid_t,
		integer, dimension(3), intent(in)	shape_x,
		integer, intent(in)	idx,
		integer, intent(in)	idx_t,
		integer, intent(in)	comm
	)

Global (parallel) transform of grid data.

Definition at line 132 of file fft_fftw_mod.F90.

References mpi_comm_size(), and transpose().

Referenced by poisson::cos_test(), poisson::shuffle_test(), poisson::spectral_solve(), and poisson::transpose_test().

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real(dp) function, public fft::wavenumber	(	integer, intent(in)	i,
		integer, intent(in)	N,
		real(dp), intent(in)	L,
		integer, intent(in)	kind
	)

Get the wavenumber of the ith mode.

Parameters

[in]	i	index of mode
[in]	n	number of modes in transform
[in]	l	Length of domain in transform
[in]	kind	Type of transform

Definition at line 107 of file fft_fftw_mod.F90.

Referenced by poisson::poisson_kernel().

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Member Data Documentation

integer fft::n_r2r_plans = 0

private

Definition at line 23 of file fft_fftw_mod.F90.

integer, parameter fft::nplans = 10

private

Definition at line 22 of file fft_fftw_mod.F90.

integer, parameter, public fft::p_backward = FFTW_HC2R

Definition at line 32 of file fft_fftw_mod.F90.

integer, parameter, public fft::p_forward = FFTW_R2HC

Definition at line 31 of file fft_fftw_mod.F90.

integer(c_int), dimension(nplans) fft::r2r_plan_kinds

private

Definition at line 27 of file fft_fftw_mod.F90.

integer, dimension(nplans) fft::r2r_plan_lengths

private

Definition at line 25 of file fft_fftw_mod.F90.

integer, dimension(nplans) fft::r2r_plan_nums

private

Definition at line 26 of file fft_fftw_mod.F90.

type(c_ptr), dimension(nplans) fft::r2r_plans

private

Definition at line 24 of file fft_fftw_mod.F90.

integer, parameter, public fft::w_backward = FFTW_REDFT01

Definition at line 30 of file fft_fftw_mod.F90.

integer, parameter, public fft::w_forward = FFTW_REDFT10

Definition at line 29 of file fft_fftw_mod.F90.

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

• fft_fftw_mod.F90