# udfGetSdData()

Return the data for a variable.

## Syntax

data = udfGetSdData( udfHd, dataName ) ;

## Type

AcuSolve User-Defined Subdomain Routine

## Parameters

udfHd
The opaque handle (pointer) which was passed to the user function.
dataName (integer)
Symbolic name of a data variable.
UDF_SD_VELOCITY
Velocity.
UDF_SD_ACCELERATION
Acceleration.
UDF_SD_PRESSURE
Pressure.
UDF_SD_TEMPERATURE
Temperature.
UDF_SD_SPECIES
Species.
UDF_SD_EDDY_VISCOSITY
Turbulence eddy viscosity.
UDF_SD_KINETIC_ENERGY
Turbulence kinetic energy.
UDF_SD_EDDY_FREQUENCY
Turbulence eddy frequency.
UDF_SD_MESH_DISPLACEMENT
Mesh displacement.
UDF_SD_MESH_VELOCITY
Mesh velocity.
UDF_SD_TURBULENCE_Y
Distance to nearest turbulence wall.
UDF_SD_TURBULENCE_YPLUS
Turbulence y+ based on distance to nearest turbulence wall and shear at that wall.

## Return Value

data (Real*)
Pointer to two dimensional real array of the requested data variable. The first (fast) dimension of the array is the number of nodes, and the second (slow) dimension is the dimension of the variable.

## Description

This routine returns the data for a variable associated with the given symbolic data name. For example,
Integer nNodes, dataDim, node ;
Real u, v, w ;
Real* data ;
...
nNodes = udfGetNSdNodes( udfHd ) ;
data = udfGetSdData( udfHd, UDF_SD_VELOCITY ) ;
for ( node = 0 ; node < nNodes ; node++ ) {
u = data[0*nNodes+node] ;
v = data[1*nNodes+node] ;
w = data[2*nNodes+node] ;
...
}

## Errors

• This routine expects a valid udfHd.
• This routine may only be called within an external code.
• dataName must be one of the values given above.
• The subdomain must contain the equation associated with the data variable.