Group Definition in Detail

This section describes details to each front end.

This page discusses:

See Also
In Other Guides
SELECT
GROUP_DEF
OPTIONS

Manual Group Definition in Tosca Structure.gui

In Tosca Structure.gui node and element groups can be defined manually using lists of node IDs or element IDs in the GROUP_DEF command:

GROUP_DEF
 ID_NAME = ndgr_name
 TYPE    = NODE
 FORMAT  = LIST
 LIST_BEGIN
 1,2,5,3000,...
END_

Changing the TYPE to ELEM assembles the elements with the numbers listed into the group. Further, a list of materials or properties can be specified using the LIST_MAT or LIST_PROP entry for FORMAT to combine all nodes or elements related to the listed materials or properties.

In combination with the command SELECT,... (see Options for Loading FE Data (OPTIONS) ) more complex group definitions are possible. To this end, the nodes (or elements) to be included in the group must first be selected according to their numbers, geometric position, belonging to a certain area etc., sometimes using several SELECT commands sequentially to collect specific nodes or elements in the selection list.

Later, the group is defined with GROUP_DEF. A typical command sequence appears as follows:

SELECT,NODE,S,...
GROUP_DEF
 ID_NAME = ndgr_name
 TYPE    = NODE
 FORMAT  = SELECTED
END_

The group is given a unique user-defined name.

In addition, it is possible to combine and subtract existing groups (either nodes or elements) to create new groups.

For combining groups (GroupD = GroupA + GroupB + GroupC):


GROUP_DEF
 ID_NAME = GroupD
 TYPE    = ELEM
 FORMAT  = LIST_GROUP
 LIST_BEGIN  
GroupA, GroupB, GroupC
END_

For subtracting groups (GroupD = GroupA - GroupB - GroupC):


GROUP_DEF
 ID_NAME = GroupD
 TYPE    = ELEM
 FORMAT  = LIST_SUBTRACT_GROUP
  LIST_BEGIN
GroupA, GroupB, GroupC
END_

White Space in Group Names

SIMULIA Tosca Structure now supports white space in group names.

Example: Having an FE input file with a group definition like "Group One," then Tosca refers to it with the origin name, including the white space. Be careful, the Tosca behavior has changed in this point: In previous releases, the white space was replaced by an underscore "_" and the group was referenced with "Group_One" (consider the underscore _). For backward compatibility reasons, two groups are created if a group name contains blanks: The first group has the blanks in its name and the second group name is with underscores "_". This behavior can be turned off by using 

OPTIONS
 GROUP_NAME_COMPATIBILITY = NO
END_

Special Characters in Group Names

SIMULIA Tosca Structure supports group names in the following format using quotation marks, parentheses, and white spaces. 


GROUP = “group name (1)”