kml_fft(f)_mpi_local_size_many

Describes the size and location of the local process data and calculates the space to be allocated.

Interface Definition

C interface:

ptrdiff_t kml_fft_mpi_local_size_many(int rank, const ptrdiff_t *n, ptrdiff_t howmany, ptrdiff_t block0, MPI_Comm comm, ptrdiff_t *local_n0, ptrdiff_t *local_0_start);

ptrdiff_t kml_fftf_mpi_local_size_many(int rank, const ptrdiff_t *n, ptrdiff_t howmany, ptrdiff_t block0, MPI_Comm comm, ptrdiff_t *local_n0, ptrdiff_t *local_0_start);

ptrdiff_t kml_ffth_mpi_local_size_many(int rank, const ptrdiff_t *n, ptrdiff_t howmany, ptrdiff_t block0, MPI_Comm comm, ptrdiff_t *local_n0, ptrdiff_t *local_0_start);

Return Value

The function returns a value of the ptrdiff_t type, indicating the number of elements to be allocated.

Parameters

Parameter	Data Type	Description	Input/Output
rank	ptrdiff_t	Number of dimensions of the data to be processed.	Input
n	const ptrdiff_t *	Indicates an array whose dimension is rank, including the size of each dimension in the data array. The constraint is n[i] ≥ 1, for i in 0 to rank - 1.	Input
howmany	ptrdiff_t	Indicates how many transforms are needed.	Input
block0	ptrdiff_t	Specifies the size of the block.	Input
comm	MPI_Comm	MPI communicator handle.	Input
sign	int	Matches the parameter passed during plan creation.	Input
flags	unsigned int	Matches the parameter passed during plan creation.	Input
local_n0	ptrdiff_t*	Size of local process data.	Output
local_0_start	ptrdiff_t*	Offset of the local process data relative to the start point of the global data.	Output

Dependencies

C: "kfft-mpi.h"

Examples

See kml_fft(f/h)_mpi_plan_many_dft.

Parent topic: MPI Local Size Functions