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-ignore_layers 0|1 : By default the current preference value is used. If 0 nodes on different layers won't be joined.
mesh_boundary
GiD_Tools mesh mesh_boundary ?-separe_by 0|1|2|3? <element_ids>
To calculate the faces or the boundary of a selection of elements.
-separe_by can be
0 (default) to ignore layers and materials of elements calculating the boundary
1 to consider boundary a face between two elements with different layer
2 to consider boundary a face between two elements with different material
3 to consider boundary a face between two elements with different layer or material
<element_ids> is the list of element ids to calculate its boundary. All elements must be of the same type and number of nodes.
For example can be set with the ids of the elements of a layer named $layer_name with [GiD_Mesh list -layer $layer_name element]