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Subsection 3.8.2: ElementData Up Section 3.8: MeshData Section Subsection 3.8.4: EdgeData

### 3.8.3 SurfaceData

This section allows users to define data that can be mapped to the surfaces of certain boundary conditions and loads. This section only defines user-defined data maps, i.e. the name, data_type and data_format attributes must be used. The surface is defined via the surface attribute.
<SurfaceData name="values" surface="surface1">
<face lid="1">1.23</face>
<face lid="2">3.45</face>
</SurfaceData>

The surface definition is defined in the Mesh section. Note that the ids refer to the local ids of the surface facets. By default, the scalar data type and const data format are assumed so only one value per facet is expected. Other data types and formats can be specified with the data_type and data_format attributes.
<SurfaceData name="data" data_type="vec3" surface="surface1">
<face lid="1">0.0, 1.0, 0.0</face>
<face lid="2">0.0, 2.0, 0.0</face>
</SurfaceData>

Optionally, the surface data may be described with a mathematical expression as a function of the initial coordinates (X,Y,Z) of the centroid of each face:
<SurfaceData name="inlet" data_type="scalar" generator="math" surface="surface1">
$2*(1-X^2-Y^2)$
</SurfaceData>

Subsection 3.8.2: ElementData Up Section 3.8: MeshData Section Subsection 3.8.4: EdgeData