openfoam/src/randomProcesses/fft/fft.H

109 lines
2.8 KiB
C++

/*---------------------------------------------------------------------------*\
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration |
\\ / A nd | Copyright (C) 2011 OpenFOAM Foundation
\\/ M anipulation | Copyright (C) 2016 OpenCFD Ltd.
-------------------------------------------------------------------------------
License
This file is part of OpenFOAM.
OpenFOAM is free software: you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with OpenFOAM. If not, see <http://www.gnu.org/licenses/>.
Class
Foam::fft
Description
Fast fourier transform using the fftw library.
The complex transform field is returned in the field supplied. The
direction of transform is supplied as an argument (-1 = forward, 1 =
reverse). The dimensionality and organisation of the array of values
in space is supplied in the nn indexing array.
SourceFiles
fft.C
\*---------------------------------------------------------------------------*/
#ifndef fft_H
#define fft_H
#include "complexFields.H"
#include "labelList.H"
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
namespace Foam
{
class fft
{
public:
enum transformDirection
{
FORWARD_TRANSFORM = -1,
REVERSE_TRANSFORM = 1
};
static void transform
(
complexField& field,
const labelList& nn,
transformDirection fftDirection
);
static tmp<complexField> forwardTransform
(
const tmp<complexField>& field,
const labelList& nn
);
static tmp<complexField> reverseTransform
(
const tmp<complexField>& field,
const labelList& nn
);
static tmp<complexVectorField> forwardTransform
(
const tmp<complexVectorField>& field,
const labelList& nn
);
static tmp<complexVectorField> reverseTransform
(
const tmp<complexVectorField>& field,
const labelList& nn
);
};
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
} // End namespace Foam
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
#endif
// ************************************************************************* //