LOWER_D
This suite of commands creates and handles the lower dimension structures associated with a mesh.  The existing mesh is labeled 'd0'.  The next lower dimension mesh 'd1' and so on.  For an original 3D mesh, the d1 structures are the surfaces (2D) separating material regions, the d2 structures are the lines separating the d1 surfaces and the d3 structures are the nodes at the ends of the d2 lines.
Several new attributes are created which belong the original mesh object:
 
name type length
d0_nnodes_topo

 

VINT, nnodes

 

0 = interior
1 = surface node
2 = line node
3 = line end node
d1_nnodes INT, scalar number of nodes in this structure
d1_elements INT, scalar number of elements in this structure
d1_nef_cmo INT, scalar number of facets/element in this structure
d1_nee_cmo INT, scalar number of edges/element in this structure
d1_nen_cmo INT, scalar number of nodes/element in this structure
d1_jtet_cycle_max INT, scalar the longest jtet cycle in this structure
d1_itettyp VINT d1_elements element type
d1_itetclr VINT d1_elements element selection number
d1_itet off VINT d1_elements offset to d1_itet
d1_jtet off VINT d1_elements offset to d1_jtet
d1_itet VINT d1_elements xd1_neu_cmo list of nodes for each element
d1_jtet VINT d1_elements xd1_nef_cmo list of face neighbors
d1_elm_d0 VINT d1_elements  elements face # in original mesh that this element came from
d2_nnodes INT, scalar number of nodes in this structure
d2_elements INT, scalar number of elements in this structure
d2_nef_cmo INT, scalar number of facets/element in this structure
d2_nee_cmo INT, scalar number of edges/element in this structure
d3_nen_cmo INT, scalar number of nodes/element in this structure
d2_jtet_cycle_max INT, scalar the longest jtet cycle in this structure
d2_itettyp VINT d2_elements element type
d2_itetclr VINT d2_elements element material number
d2_itet off VINT d2_elements offset to d2_itet
d2_jtet off VINT d2_elements offset to d2_jtet
d2_itet VINT d2_elements xd2_neu_cmo list of nodes for each element
d2_jtet VINT d2_elements xd2_nef_cmo list of face neighbors 
d2_elm_d1 VINT d2_elements element & face that this element came from in next higher level structure
d3_nnodes INT, scalar number of nodes in this structure
lower_d_flag INT, scalar 0= no lower d structure exist
=1 lower_d structures exist and are valid
=2 lower_d structures not valid

The above set of attributes are created if the original mesh is 3D.  If the original mesh is 2D then the d1 structures are created, but the d2 structures are simply the d2_nnodes.  If the original mesh is 1D, then only the d1_nnodes structure is created.

At the time the lower_d structures are created color table attributes: d0_clrtab, d0_nclrs, .. are also created.

FORMAT:
lower_d / create/ [cmo_name]
  create lower_d structures in mesh object
lower_d / release/ [cmo_name]
 release lower_d structures
lower_d / extract/ [cmo_name/cmo1/cmo2/cmo2]
 create lower_d structures into named mesh objects cmo1, cmo2, cmo3.
lower_d / filter/ [cmo_name] /[iclr1 | itp | imt | clr ] / value [ and | or | new ]
  these commands are advised for expert users only.
EXAMPLES: