COMSOL Multiphysics™

femstatic
Purpose
femstatic
Solve stationary PDE problem with a nonlinear or linear solver.
Syntax
Description
fem.sol = femstatic(fem,...)
fem = femstatic(fem,'Out',{'fem'},...)
fem.sol = femstatic(fem) solves a stationary PDE problem using either a linear
or nonlinear solver.
fem.sol = femstatic(fem,'pname','P', plist',list,...) solves a
stationary PDE problem for several values of the parameter P. The values of the
parameter P are given in the vector list.
The PDE problem is stored in the (possibly extended) FEM Structure fem. See
femstruct for details.
The function femstatic accepts the following property/value pairs:
TABLE 1-38: VALID PROPERTY/VALUE PAIRS
PROPERTY VALUE DEFAULT DESCRIPTION
Nonlin off | on | auto auto Use the nonlinear solver
Out
fem | sol | u | plist
| stop | solcompdof
| Kc | Lc | Null | Nnp
| ud | uscale |
nullfun |
symmetric | nonlin
| cell array of these
strings
sol
Output variables
This solver uses the nonlinear solver described in femnlin if nonlin is on, and it
uses the linear solver described in femlin if nonlin is off. If nonlin is set to auto
an analysis is performed to automatically detect if the problem can be solved with
the linear solver.
In addition to the properties listed above, also the properties for femlin or femnlin
are supported, depending on which solver is used. For example, the linear solver
does not support the properties Augcomp, Augsolver, Augtol, Augmaxiter,
Porder, and Ntol. Similarly, the nonlinear solver does not support the properties
In and Itol. Furthermore, the properties described in the entry femsolver are
supported.
The automatic nonlinear/linear detection works in the following way. The linear
solver is called if the residual jacobian matrix (the stiffness matrix, K) and the
constraint jacobian matrix (the constraint matrix, N) are both found not solution
164 | CHAPTER 1: COMMAND REFERENCE