FE_Element is a base class, subtypes of which are used to
enforce the constraints on the domain. An object of type FE_Element
represents an element of the domain in the analysis. It enforces no
constraints other than single point homogeneous boundary conditions,
imposed on any of the elements nodes. It provides a similar interface
to that of an Element but modified to provide features useful to an
Analysis class. The FE_Element is responsible for:
- Holding information about the mapping between equation numbers
and the degrees-of-freedom at the
element ends, this mapping is determined from the DOF_Group objects
associated with the elements Node objects.
- Providing methods to
allow the integrator to combine the elements stiffness, mass and
damping matrices into the elements contribution to the structure
tangent matrix and the elements resisting force to the structure
unbalance. Obtaining the stiffness, damping and mass matrices from the
elements.
- Providing methods so other forces can be
determined.
While the FE_Element class is
associated with an element in the domain, subclasses do not have to
be. It is the subclasses that are used to implement the constraints
imposed on the nodal displacements in the domain.
FE_Element(