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Finite Element Spaces

The definition
define fespace <name> <flaglist>
defines the finite element space <name>. Example:
define fespace v -order=2 -dim=3
There are various classes of finite element spaces. Default are continuous, nodal-valued finite element spaces. The following define flags select the type of spaces
non of the flags below continuous nodal finite element space
-hcurl H(curl) finite elements (Nedelec-type, edge elements)
-hdiv H(div) finite elements (Raviart-Thomas, face elements)
-l2 non-continuous elements, element by element
-l2surf element by element on surface
-h1ho Arbitrary order continuous elements
-hcurlho Arbitrary order H(curl) elements
-hdivho Arbitrary order H(div) elements
-l2ho Arbitrary order non-continuous elements

The following flags specify the finite element spaces

-order=<num> Order of finite elements
-dim=<num> Number of fields (number of copies of fe), 2 for 2D elasticity
-vec set -dim=spacedim
-tensor set -dim=spacedim*spacedim
-symtensor set -dim=spacedim * (spacedim+1) / 2, (symmetric stress tensor)
-complex complex valued fe-space

A compound fe-space combines several fe-spaces to a new one. Useful, e.g., for Reissner-Mindlin plate models containing the deflection w and two rotations beta:

fespace vw -order=2
fespace vbeta -order=1
fespace v -compound -spaces=[vw,vbeta,vbeta]

The fespace maintains the degrees of freedom. On mesh refinement, the space provides the grid transfer operator (prolongation). High order fe spaces maintain a lowest-order fespace of the same type for preconditioning.



Subsections
next up previous contents
Next: H1-Finite Element Space Up: Reference Manual Previous: Coefficient functions   Contents
Joachim Schöberl 2004-11-17