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Linear-forms

A linear form is defined by

define linearform <name> <flaglist>
integrator1
integrator2
integrator3
...
Example
define linearform f -fespace=v
source coef_f
neumann coef_g

A linear-form is always defined as sum over integrators. A linear-form maintains the right hand side vector.

The following flags are defined
-fespace=<name> bilinear form is defined on fe space <name>

An integrator is defined as

token <coef1> <coef2> ... <flaglist>
Example:
source coef_fy -comp=2
The <coefi> refers to a coefficient function defined above. It provides the coefficients defined sub-domain by dub-domain for integrators defined on the domain (e.g., source), or, the coefficient boundary-patch by boundary-patch for integrators defined on the surface (e.g., neumann).

Allowed flags are
-order=num use integration rule of order num. Default order is computed form element order.
-comp=num use scalar integrator as component num for system (e.g., penalty term for y-displacement). num=0 adds integrator to all components.
-normal add integrator in normal direction (surface load in normal direction)

The integrator tokens are
source f $\int_\Omega f v   dx$
neumann g $\int_\Gamma g v   ds$
sourceedge jx jy jz $\int_\Omega j \cdot v   dx$ for 3D $H(curl)$ spaces
neumannedge jx jy jz $\int_\Gamma (n \times j) \cdot (n \times v)   ds$ for 3D $H(curl)$ spaces
curledge f $\int_\Omega f (\nabla \times v_z)   dx$ for 2D $H(curl)$ spaces
curlboundaryedge f $\int_\Gamma f n \cdot (\nabla \times v)   ds$ for 3D $H(curl)$ spaces


next up previous contents
Next: Preconditioners Up: Reference Manual Previous: Bilinear-forms   Contents
Joachim Schoeberl 2002-07-15