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fftw_plan fftw_plan_many_dft_r2c(int rank, const int *n, int howmany, Chris@19: double *in, const int *inembed, Chris@19: int istride, int idist, Chris@19: fftw_complex *out, const int *onembed, Chris@19: int ostride, int odist, Chris@19: unsigned flags); Chris@19: fftw_plan fftw_plan_many_dft_c2r(int rank, const int *n, int howmany, Chris@19: fftw_complex *in, const int *inembed, Chris@19: int istride, int idist, Chris@19: double *out, const int *onembed, Chris@19: int ostride, int odist, Chris@19: unsigned flags); Chris@19:Chris@19:
Chris@19: Like fftw_plan_many_dft, these two functions add howmany,
Chris@19: nembed, stride, and dist parameters to the
Chris@19: fftw_plan_dft_r2c and fftw_plan_dft_c2r functions, but
Chris@19: otherwise behave the same as the basic interface.
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The interpretation of howmany, stride, and dist are
Chris@19: the same as for fftw_plan_many_dft, above. Note that the
Chris@19: stride and dist for the real array are in units of
Chris@19: double, and for the complex array are in units of
Chris@19: fftw_complex.
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If an nembed parameter is NULL, it is interpreted as what
Chris@19: it would be in the basic interface, as described in Real-data DFT Array Format. That is, for the complex array the size is assumed to be
Chris@19: the same as n, but with the last dimension cut roughly in half.
Chris@19: For the real array, the size is assumed to be n if the transform
Chris@19: is out-of-place, or n with the last dimension “padded” if the
Chris@19: transform is in-place.
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If an nembed parameter is non-NULL, it is interpreted as
Chris@19: the physical size of the corresponding array, in row-major order, just
Chris@19: as for fftw_plan_many_dft. In this case, each dimension of
Chris@19: nembed should be >= what it would be in the basic
Chris@19: interface (e.g. the halved or padded n).
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Arrays n, inembed, and onembed are not used after
Chris@19: this function returns. You can safely free or reuse them.
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