ActivateElementsUserObjectBase

The ActivateElementsUserObjectBase class is for activating (adding) an element by moving the element from an "inactive" subdomain to the "active" subdomain. There are two metrics for activating an element, i.e., by function path and by coupled variable value, which are implemented in the classes ActivateElementsByPath and ActivateElementsCoupled, respectively.

This mesh modifier updates the boundary information due to the addition of elements across subdomains. User can save this boundary information by passing the changed boundary name to expand_boundary_name in the input block. Note that current implementation does not de-activate an element once the element is activated.