COMSOL Multiphysics™

femsolver
This alternative uses a temporary hierarchy that is constructed by the solver. Since
the solver also constructs a temporary xmesh, this alternative wastes some memory.
Alternative 2:
fem = femstatic(fem,'linsolver','gmg','out','fem');
Here, the solver uses a temporary hierarchy, but there is only one xmesh. If another
such solver call is made, fem.xmesh should first be deleted to save some memory.
Alternative 3:
fem =
femstatic(fem,'linsolver','gmg','mgkeep','on','out','fem');
Now the generated hierarchy is kept, which means that you can reuse it in a
subsequent call:
fem.sol = femstatic(fem,'linsolver','gmg');
Alternative 4:
fem = meshcaseadd(fem);
fem.xmesh = meshextend(fem);
fem.sol = femstatic(fem,'linsolver','gmg');
The meshcaseadd call adds mesh cases to the FEM structure. These form the
multigrid hierarchy in the solver.
Compatibility
COMSOL Multiphysics 3.2: The default of the Conjugate property has been
changed to off.
The following FEMLAB 2.3 general solver properties are obsolete in FEMLAB 3.0:
TABLE 1-36: OBSOLETE PROPERTY/VALUE PAIRS
PROPERTY VALUES IMPLICATION
Initmethod weak | pointwise | No longer supported
local | dof
Itsolv gbit | gmres | tfqmr Use Linsolver property.
Jacobian lumped | numeric No longer supported
Linsolver matlab | superlu Uses default direct solver
Maxlinit vector with 2
components
Ignores second component and warns
160 | CHAPTER 1: COMMAND REFERENCE