Visible to Intel only — GUID: GUID-DFA327CF-25F1-4591-954B-DDB37FC0E3E3
Visible to Intel only — GUID: GUID-DFA327CF-25F1-4591-954B-DDB37FC0E3E3
DftiCreateDescriptorDM
Allocates memory for the descriptor data structure and preliminarily initializes it.
Syntax
Status = DftiCreateDescriptorDM(comm, handle, v1, v2, dim, size)
Status = DftiCreateDescriptorDM(comm, handle, v1, v2, dim, sizes)
Include Files
- mkl_cdft.f90
Input Parameters
- comm
- MPI communicator, e.g. MPI_COMM_WORLD.
- v1
- Precision of the transform.
- v2
- Type of the forward domain. Must be DFTI_COMPLEX for complex-to-complex transforms or DFTI_REAL for real-to-complex transforms.
- dim
- Dimension of the transform.
- size
- Length of the transform in a one-dimensional case.
- sizes
- Lengths of the transform in a multi-dimensional case.
Output Parameters
- handle
- Pointer to the descriptor handle of transform. If the function completes successfully, the pointer to the created handle is stored in the variable.
Description
This function allocates memory in a particular MPI process for the descriptor data structure and instantiates it with default configuration settings with respect to the precision, domain, dimension, and length of the desired transform. The domain is understood to be the domain of the forward transform. The result is a pointer to the created descriptor. This function is slightly different from the "initialization" function DftiCommitDescriptorDM in a more traditional software packages or libraries used for computing the FFT. This function does not perform any significant computation work, such as twiddle factors computation, because the default configuration settings can still be changed using the function DftiSetValueDM.
The value of the parameter v1 is specified through named constants DFTI_SINGLE and DFTI_DOUBLE. It corresponds to precision of input data, output data, and computation. A setting of DFTI_SINGLE indicates single-precision floating-point data type and a setting of DFTI_DOUBLE indicates double-precision floating-point data type.
The parameter dim is a simple positive integer indicating the dimension of the transform.
In Fortran, length is an integer or an array of integers.
Return Values
The function returns DFTI_NO_ERROR when completes successfully. In this case, the pointer to the created descriptor handle is stored in handle. If the function fails, it returns a value of another error class constant (for the list of constants, refer to Error Codes).
Interface
INTERFACE DftiCreateDescriptorDM INTEGER(4) FUNCTION DftiCreateDescriptorDMn(C,H,P1,P2,D,L) TYPE(DFTI_DESCRIPTOR_DM), POINTER :: H INTEGER(4) C,P1,P2,D,L(*) END FUNCTION INTEGER(4) FUNCTION DftiCreateDescriptorDM1(C,H,P1,P2,D,L) TYPE(DFTI_DESCRIPTOR_DM), POINTER :: H INTEGER(4) C,P1,P2,D,L END FUNCTION END INTERFACE