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        list of nodes for each
                         xd1\_neu\_cmo            element
 
d1\_jtet                 VINT d1\_elements        list of face neighbors
                         xd1\_nef\_cmo            
 
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        list of nodes for each
                         xd2\_neu\_cmo            element
 
d2\_jtet                 VINT d2\_elements        list of face neighbors 
                         xd2\_nef\_cmo            
 
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: