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fftw_plan fftw_plan_guru_dft_r2c( cannam@95: int rank, const fftw_iodim *dims, cannam@95: int howmany_rank, const fftw_iodim *howmany_dims, cannam@95: double *in, fftw_complex *out, cannam@95: unsigned flags); cannam@95: cannam@95: fftw_plan fftw_plan_guru_split_dft_r2c( cannam@95: int rank, const fftw_iodim *dims, cannam@95: int howmany_rank, const fftw_iodim *howmany_dims, cannam@95: double *in, double *ro, double *io, cannam@95: unsigned flags); cannam@95: cannam@95: fftw_plan fftw_plan_guru_dft_c2r( cannam@95: int rank, const fftw_iodim *dims, cannam@95: int howmany_rank, const fftw_iodim *howmany_dims, cannam@95: fftw_complex *in, double *out, cannam@95: unsigned flags); cannam@95: cannam@95: fftw_plan fftw_plan_guru_split_dft_c2r( cannam@95: int rank, const fftw_iodim *dims, cannam@95: int howmany_rank, const fftw_iodim *howmany_dims, cannam@95: double *ri, double *ii, double *out, cannam@95: unsigned flags); cannam@95:cannam@95:
cannam@95: Plan a real-input (r2c) or real-output (c2r), multi-dimensional DFT with
cannam@95: transform dimensions given by (rank, dims) over a
cannam@95: multi-dimensional vector (loop) of dimensions (howmany_rank,
cannam@95: howmany_dims). dims and howmany_dims should point
cannam@95: to fftw_iodim arrays of length rank and
cannam@95: howmany_rank, respectively. As for the basic and advanced
cannam@95: interfaces, an r2c transform is FFTW_FORWARD and a c2r transform
cannam@95: is FFTW_BACKWARD.
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The last dimension of dims is interpreted specially:
cannam@95: that dimension of the real array has size dims[rank-1].n, but
cannam@95: that dimension of the complex array has size dims[rank-1].n/2+1
cannam@95: (division rounded down). The strides, on the other hand, are taken to
cannam@95: be exactly as specified. It is up to the user to specify the strides
cannam@95: appropriately for the peculiar dimensions of the data, and we do not
cannam@95: guarantee that the planner will succeed (return non-NULL) for
cannam@95: any dimensions other than those described in Real-data DFT Array Format and generalized in Advanced Real-data DFTs. (That is,
cannam@95: for an in-place transform, each individual dimension should be able to
cannam@95: operate in place.)
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in and out point to the input and output arrays for r2c
cannam@95: and c2r transforms, respectively. For split arrays, ri and
cannam@95: ii point to the real and imaginary input arrays for a c2r
cannam@95: transform, and ro and io point to the real and imaginary
cannam@95: output arrays for an r2c transform. in and ro or
cannam@95: ri and out may be the same, indicating an in-place
cannam@95: transform. (In-place transforms where in and io or
cannam@95: ii and out are the same are not currently supported.)
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flags is a bitwise OR (‘|’) of zero or more planner flags,
cannam@95: as defined in Planner Flags.
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In-place transforms of rank greater than 1 are currently only
cannam@95: supported for interleaved arrays. For split arrays, the planner will
cannam@95: return NULL.
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