Developer Reference for Intel® oneAPI Math Kernel Library for C

ID 766684
Date 3/31/2023
Public

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Complex MPI FFTW

Complex One-dimensional MPI FFTW Transforms

fftw_mpi_plan fftw_mpi_create_plan(MPI_Comm comm, int n, fftw_direction dir, int flags);

void fftw_mpi(fftw_mpi_plan p, int n_fields, fftw_complex *local_data, fftw_complex *work);

void fftw_mpi_local_sizes(fftw_mpi_plan p, int *local_n, int *local_start, int *local_n_after_transform, int *local_start_after_transform, int *total_local_size);

void fftw_mpi_destroy_plan(fftw_mpi_plan plan);

Argument restrictions:

  • Supported values of flags are FFTW_ESTIMATE, FFTW_MEASURE, FFTW_SCRAMBLED_INPUT and FFTW_SCRAMBLED_OUTPUT. The same algorithm corresponds to all these values of the flags parameter. If any other flags value is supplied, the wrapper library reports an error 'CDFT error in wrapper: unknown flags'.
  • The only supported value of n_fields is 1.

Complex Multi-dimensional MPI FFTW Transforms

fftwnd_mpi_plan fftw2d_mpi_create_plan(MPI_Comm comm, int nx, int ny, fftw_direction dir, int flags);

fftwnd_mpi_plan fftw3d_mpi_create_plan(MPI_Comm comm, int nx, int ny, int nz, fftw_direction dir, int flags);

fftwnd_mpi_plan fftwnd_mpi_create_plan(MPI_Comm comm, int dim, int *n, fftw_direction dir, int flags);

void fftwnd_mpi(fftwnd_mpi_plan p, int n_fields, fftw_complex *local_data, fftw_complex *work, fftwnd_mpi_output_order output_order);

void fftwnd_mpi_local_sizes(fftwnd_mpi_plan p, int *local_nx, int *local_x_start, int *local_ny_after_transpose, int *local_y_start_after_transpose, int *total_local_size);

void fftwnd_mpi_destroy_plan(fftwnd_mpi_plan plan);

Argument restrictions:

  • Supported values of flags are FFTW_ESTIMATE and FFTW_MEASURE. If any other value of flags is supplied, the wrapper library reports an error 'CDFT error in wrapper: unknown flags'.
  • The only supported value of n_fields is 1.