Developer Reference for Intel® oneAPI Math Kernel Library for Fortran

ID 766686
Date 7/13/2023
Public

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DFTI_PRECISION

The configuration parameter DFTI_PRECISION denotes the floating-point precision in which the transform is to be carried out. A setting of DFTI_SINGLE stands for single precision, and a setting of DFTI_DOUBLE stands for double precision. The data must be presented in this precision, the computation is carried out in this precision, and the result is delivered in this precision.

DFTI_PRECISION does not have a default value. Set it explicitly by calling the DftiCreateDescriptor function.

NOTE:

Fortran module MKL_DFTI also defines named constants DFTI_SINGLE_R and DFTI_DOUBLE_R, with the same semantics as DFTI_SINGLE and DFTI_DOUBLE, respectively. Do not use these constants to set the DFTI_PRECISION configuration parameter. Use them only as described in DftiCreateDescriptor.

To better understand configuration of the precision of transforms, refer to these examples in your Intel® oneAPI Math Kernel Library (oneMKL) directory:

./examples/dftf/source/basic_sp_complex_dft_1d.f90

./examples/dftf/source/basic_dp_complex_dft_1d.f90