I.3.3 Manipulation of entities stored in a Group

The class “Group” provides a large choice of methods devoted to the manipulation of the list of entities in its storage. One makes the distinction between operations that modify the content of a Group, and the operations that allow the inspection of this content.

The modification of the Group’s content can be done by calls to the following methods:

• “setEntities” takes a String argument that contains the definition of Group entities in a format similar to the format of the Patran Group session file (section I.1.2.1). All entities previously stored in the Group are erased before the conversion of the String argument. The function returns “self” (the modified Group object). As the String argument follows Patran conventions, the list of RBEs follows “MPC” keyword.
• “setEntitiesByType” has two arguments. The first argument, “TypeName” is a String object that specifies the type of entities to be added to the Group. This first argument may have four different values: “Node”, “Element”, “MPC” (for rigid body elements) or “CoordSys”. Any other argument is invalid. The second argument may have two different types:

  1.

  The second argument may be a String object containing the definition of a group in a format similar to the format of the Patran Group session file (section I.1.2.1). However, in this case, only the entities of the type selected by the “TypeName” argument are stored in the Group.

  2.

  The second argument may also be an Array of integers. Then the integers correspond to the entities added to the Group. The type of entities is specified by the “TypeName” argument.

  As for the “setEntities” method, all entities previously stored in the Group are erased before inserting the new entities.

• “addEntities” is identical to “setEntities” but the entities stored in the Group are not erased before adding the new entities. As the String argument follows Patran conventions, the list of RBEs follows “MPC” keyword.
• “addEntitiesByType” is identical to “setEntitiesByType” but the entities stored in the Group are not erased before adding the new entities.
• “removeEntities” is identical to “addEntities” but the selected entities are removed from the Group instead of being added to it. As the String argument follows Patran conventions, the list of RBEs follows “MPC” keyword.
• “removeEntitiesByType” is identical to “addEntitiesByType” but the selected entities are removed from the Group instead of being added to it.
• “clearAllEntitiesByType” has one String argument corresponding to the type of entities to be cleared from the Group. Possible arguments are “Node”, “Element”, “MPC” (for rigid body elements) or “CoordSys”.
• “importEntitiesByType” is used to insert entities in a Group by importing them from another Group, or from the entities stored in a DataBase model. The method has two or four arguments:
  • The first argument is a String corresponding to the type of entities to be inserted. Possible arguments are “Node”, “Element”, “MPC” (for rigid body elements) or “CoordSys”.
  • The Second argument is either a Group, or a DataBase.
  • the third and four arguments are integers corresponding to the range of insertion (idMin and idMax). If omitted, then all entities of the corresponding type are inserted.
• “matchWithDbEntities” is used to ensure that a Group contains only entities that are defined in a DataBase. The function has one DataBase argument. After calling this method, the entities that do not exist in the DataBase have been cancelled from the Group too.

Presently, four methods devoted to the manipulation of entities and not modifying the Group have been defined:

• “getEntitiesByType” receives one String argument corresponding to the type of entity and returns an Array of integers containing the corresponding entity indices. The four possible values of the argument are “Node”, “Element”, “MPC” (for rigid body elements) and “CoordSys”.
• “getNbrEntitiesByType” receives one String argument corresponding to the type of entity and returns an integer corresponding to the number of entities of the specified type contained in the Group. The four possible values of the argument are “Node”, “Element”, “MPC” (for rigid body elements) and “CoordSys”.
• “getNbrEntities” has no argument and returns an Array of four integer corresponding to the number of entities of each of the following types, and in the same order as: “CoordSys”, “Element”, “Node” and “MPC” (for rigid body elements).
• “containsEntity” allows to check whether a given entity belongs to the Group. The method has two arguments:
  • The first argument is a String corresponding to the type of entities to be inserted. Possible arguments are “Node”, “Element”, “MPC” (for rigid body elements) or “CoordSys”.
  • The second integer argument is the entityId.

  The function returns a bool value.

A FeResPost Group cannot contain Nastran MPCs.