Developer Reference for Intel® oneAPI Math Kernel Library - C

Developer Reference

Contents

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.h
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.
For
one-dimensional transforms, length is a single integer value of the parameter
size
 having type
MKL_LONG
; for multi-dimensional transforms, length is supplied with the parameter
sizes
, which is an array of integers having type
MKL_LONG
.
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).
Prototype
   
MKL_LONG DftiCreateDescriptorDM(MPI_Comm,DFTI_DESCRIPTOR_DM_HANDLE*,
   enum DFTI_CONFIG_VALUE,enum DFTI_CONFIG_VALUE,MKL_LONG,...);
   

Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.