The button includes options to add different types of groups of objects. Simulation objects can be organized into various types of groupings.
A container group is the simplest type and can contain all object types as well as other groups. This object acts like a simple folder allowing the user to collapse and expand its contents in the object tree. Its only user setting is a position offset in x,y,z for all contained objects.
For Finite Element IDE, Container Groups sit under the solver region and cannot contain structures.
Structure groups are one step above container groups in that they allow scripting commands of structures properties. This group contains user-generated variables and scripts that can be utilized to edit and set up parts of the structure. For example, a script can be set up to insert many circles to create a photonic crystal cavity of a certain shape and size. See the Structure groups tutorial for more information. Structure groups can contain other structure groups.
Analysis groups are the most advanced of the three groups. It is a two-part group: setup and analysis. In the setup portion, it acts like a structure group allowing users to insert and edit structures through a script except that it has been extended to include all objects. User can create a script that modifies a simulation region span, source locations and analysis monitor properties. In the analysis portion, it is used to process monitor data and create output data variables once a simulation has been run. It is possible for analysis groups to contain other groups. As an example, the top level object 'model' that represents the entire simulation, is an analysis group. Please see Analysis groups for more examples.