Rheolef
7.2
an efficient C++ finite element environment
|
basis name [element] [options]
View a finite element polynomial basis on a given reference element (see reference_element
). Alternatively, it could show the interpolation nodes.
basis P5 t basis P5[warburton] t basis P5[warburton,monomial] t basis 'trace(P3d)' t basis P3 t -node basis P5 t -node-side 0 basis P5 t -node-side 1 basis P3 T -node basis B7 t basis S7 t basis RT0 t basis RT3 t -node basis "trace_n(RT5d)" t -node basis P3d T -node-side 1 basis 'trace_n(RT5d)' T -node-side 1
The basis name argument is specified as for the space
and basis
constructor class argument (see space
and basis
). The element argument is one of e
, t
, q
, T
, P
, H
(see reference_element
). The gnuplot
render is used for visualization.
-raw
-fem
A raw basis is used for computing the Vandermonde matrix and building the Lagrange basis. The raw basis is either
monomial
,Dubiner
orBernstein
whileDubiner
is the default. This raw basis is hiden by default: it is represented by using the-raw
option while-fem
switch back to the default finite element basis representation. When the basis family is eitherM
, formonomial
orD
forDubiner
, there is no ambiguity, and the-raw
option could be omitted. Conversely, when the basis family isB
, forBernstein
, then, there is an ambiguity and this option should be used.
Here is an example of raw basis visualization:
basis M4 t basis D5 e basis B5 e -raw
Here, the -raw
option is used to disambiguate
between the Bernstein basis as finite element basis and the Bernstein basis as a raw basis.
The basis
command supports several modes of visualization:
-ndof
Print the basis size, i.e. the number of degrees of freedom (ndof).
-poly
Represents the polynomial functions in elevation, for 1D and 2D elements (3D elements visualization not yet supported). All basis polynomials are showed in an animation.
-node
Represents the node location, with distinct colors for each dimension associated to.
-node-side
Represents the node location, restricted on a specific side.
-[no]verbose
Print messages related to graphic files created and command system calls (this is the default).
-[no]clean
Clear temporary graphic files (this is the default).
-[no]execute
Execute graphic command (this is the default). The
-noexecute
variant is useful in conjunction with the-verbose
and-noclean
options in order to modify some render options by hand.
Polynomial visualization in 3D are not yet supported: future development will use paraview with volume mode and animation for scanning all basis polynomials.
This documentation has been generated from file fem/lib/basis.cc