# GetValueDM

Gets the value of one particular configuration parameter.

## Syntax

Fortran:

Status = DftiGetValueDM(handle, param, value)

C/C++:

status = DftiGetValueDM(handle, param, &value);

## Input Parameters

handle
  The descriptor handle. Must be valid, that is, created in a call to DftiCreateDescriptorDM.
param
  Name of a parameter to be retrieved from the descriptor. See Table “Retrievable Configuration Parameters” for the list of available parameters.

## Output Parameters

value
  Value of the parameter.

## Description

This function gets the configuration value of one particular configuration parameter. The configuration parameter is one of the named constants listed in the table below, and the configuration value is the corresponding appropriate type, which can be a named constant or a native type. Possible values of the named constants can be found in Table “Settings for Discrete Configuration Parameters”.

Retrievable Configuration Parameters
Parameter Name | Data Type | Description
--- | --- | ---
DFTI_PRECISION | Named constant | Precision of computation, input data and output data.
DFTI_DIMENSION | Integer scalar | Dimension of the transform
DFTI_LENGTHS | Array of integer values | Array of lengths of the transform. Number of lengths corresponds to the dimension of the transform.
DFTI_FORWARD_SCALE | Floating-point scalar | Scale factor of forward transform.
DFTI_BACKWARD_SCALE | Floating-point scalar | Scale factor of backward transform.
DFTI_PLACEMENT | Named constant | Placement of the computation result.
DFTI_COMMIT_STATUS | Named constant | Shows whether descriptor has been committed.
DFTI_FORWARD_DOMAIN | Named constant | Forward domain of transforms (In the current implementation of the cluster FFT interface, the value is always `DFTI_COMPLEX`.).
`DFTI_ORDERING` | Named constant | Scrambling of data order.
CDFT_MPI_COMM | Type of MPI communicator | MPI communicator used for transforms.
CDFT_LOCAL_SIZE | Integer scalar | Necessary size of input, output, and buffer arrays in data elements.
CDFT_LOCAL_X_START | Integer scalar | Row/element number of the global array that corresponds to the first row/element of the local array. For more information, see Distributing Data among Processes.
CDFT_LOCAL_NX | Integer scalar | The number of rows/elements of the global array stored in the local array. For more information, see Distributing Data among Processes.
CDFT_LOCAL_OUT_X_START | Integer scalar | Element number of the appropriate global array that corresponds to the first element of the input or output local array in a 1D case. For details, see Distributing Data among Processes.
CDFT_LOCAL_OUT_NX | Integer scalar | The number of elements of the appropriate global array that are stored in the input or output local array in a 1D case. For details, see Distributing Data among Processes.

## Return Values

The function returns `DFTI_NO_ERROR` when completes successfully. If the function fails, it returns a value of another error class constant (for the list of constants, refer to Error Codes).

## Interface and Prototype

! Fortran Interface

INTERFACE DftiGetValueDM

INTEGER(4) FUNCTION DftiGetValueDM(h, p, v)

TYPE(DFTI_DESCRIPTOR_DM), POINTER :: h

INTEGER(4) :: p, v

END FUNCTION

INTEGER(4) FUNCTION DftiGetValueDMar(h, p, v)

TYPE(DFTI_DESCRIPTOR_DM), POINTER :: h

INTEGER(4) :: p, v(*)

END FUNCTION

INTEGER(4) FUNCTION DftiGetValueDMd(h, p, v)

TYPE(DFTI_DESCRIPTOR_DM), POINTER :: h

INTEGER(4) :: p

REAL(8) :: v

END FUNCTION

INTEGER(4) FUNCTION DftiGetValueDMs(h, p, v)

TYPE(DFTI_DESCRIPTOR_DM), POINTER :: h

INTEGER(4) :: p

REAL(4) :: v

END FUNCTION

END INTERFACE

/* C/C++ prototype */

long DftiGetValueDM(DFTI_DESCRIPTOR_DM_HANDLE handle, int param,...);

Parent topic: Descriptor Configuration Functions