Mesh  

mass_properties

GiD_Tools mesh mass_properties <tetrahedra_ids> | -boundary_elements <triangle_ids>
To calculate the mass properties of volume, gravity center and inertia tensor of a volume, defined by a selection of tetrahedra or the selection of the triangles bounding the volume.
<tetrahedra_ids> A list of integer ids of the tetrahedra of the volume to be computed
<triangle_ids> A list of integer ids of the triangles that enclose a volume, with normals pointing inside.

It returns a list with 3 items: mass {center_x center_y center_z} {Ixx Iyy Izz Ixy Iyz Ixz}
the 6 inertia values describe the symmetric 3x3 inertia tensor

Ixx Ixy Ixz
Ixy Iyy Iyz
Ixz Iyz Izz

Note: this command is similar to GiD_Info listmassproperties, but this command is not computing inertias

intersectvolumeslines

GiD_Tools mesh intersectvolumeslines <group_lines>
Specialized command that calculate the intersections of the line elements that belong to the group named <group_lines> with the current mesh of hexahedra.

collapse

GiD_Tools mesh collapse ?-tolerance <tolerance>? ?-try_to_maintain_boundary 0|1? ?-ignore_layers 0|1? nodes <node_ids>|elements <element_ids>|mesh")

To collapse the entities of the mesh close to the tolerance distance. By default the current preference value is used.

-try_to_maintain_boundary 0|1 : 1 default to set more priority to nodes on the boundary to preserve them.

-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]

It is a command similar to GiD_Geometry get surface|volume <id> mesh_boundary

Will return the information of the boundary of the mesh of the geometric entity <id> as a list: {element_type element_num_nodes connectivities}
element_type: string
element_num_nodes: integer with the amount of nodes of an element (all mesh elements are of same type). Can be also a quadratic mesh, whit more nodes than the linear ones of the corners.
connectivities: objarray with element_num_nodes*num_elements of int with the connectivities of the elements (one-based)
a volume with a mesh of prisms or pyramid will have as boundary a mix of quadrilateral and triangles, all are expressed as quadrilaterals (triangles will write the 4^th node repeating the last id)