# udfGetSdDataName()

Return a data variable name in the subdomain.

## Syntax

dataName = udfGetSdDataName( udfHd, dataId ) ;

## Type

AcuSolve User-Defined Subdomain Routine

## Parameters

- udfHd
- The opaque handle (pointer) which was passed to the user function.
- dataId (integer)
- Index from 0 to nNames -1.

## Return Value

- dataName (integer)
- Symbolic name corresponding to the data index.
- 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.

## Description

This routine returns a symbolic data name in the current subdomain. For
example,

```
Integer nNames, dataName, dataId ;
...
nNames = udfGetNSdDataNames( udfHd ) ;
for ( dataId = 0 ; dataId < nNames ; dataId++ ) {
dataName = udfGetSdDataName( udfHd, dataId ) ;
if ( dataName == UDF_SD_VELOCITY ) {
...
}
}
```

## Errors

- This routine expects a valid udfHd.
- This routine may only be called within an external code.
- dataId must be from 0 to nNames-1.