Patran Reference Manual-All About Groups

5.1 Group Concepts and Definitions
A group is a named collection of selected geometric or finite element entities. The primary purpose of
grouping entities within a larger model is to create easily manageable subsets that can be visually isolated
for various modeling and post-processing tasks.
A model may contain any number of groups, and any entity may be associated with more than one group.
When an entity is added to or removed from a group, other groups will not be affected.
Groups become permanent members of a model’s database. A group, named default_group, exists in any
new database; until you define and activate new groups, all new entities automatically become members
of this group.
The defining features of a group are:
-Name
-Member entities
-Status
-Attributes

Group Membership
A group may consist of any combination of geometric and finite element entities. Other design features,
such as coordinate frames, materials, element properties, loads and boundary conditions, fields, and
analysis results cannot be categorized as group members even though they are associated with group
members.
Group Status
The status of a group may be:
-current or not current
-posted or unposted
-target group
Current Group
The current group is the active and visible group that receives all newly created entities. Any group may
be selected as current, however only one group may be current at any given time. The name of the current
group is displayed as part of the Viewport Banner.
Each viewport has its own current group but the only active current group is that of the current viewport
(see also Current Viewport, 319).

 

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