Quadrangle#

To define a quadrangle, give the 4 vertices (no edge crossing and not degenerated)

Figure made with TikZ

Figure made with TikZ

There is a parameter for each of them:_v1, _v2, _v3 and _v4. These parameters take 2D or 3D points.

_nnodes can take one single value, an explicit list of 4 values or a Numbers object and _hsteps can take one real value, an explicit list of 4 real values or a Reals object. If required, give names of the main domain and side domains as explained in Geometry definition:

Quadrangle q1(_v1=Point(0.,0.), _v2=Point(2.,0.), _v3=Point(2.,1.), _v4=Point(0.,1.),
              _nnodes={20, 10, 20, 10}, _domain_name="Omega", _side_names="Gamma");

Let’s summarize information about geometrical keys on quadrangles:

key(s)

authorized types

examples

_v1 , _v2 , _v3 , _v4

Point

_v1=Point(0.,0.), _v4=Point(0.,0.,0.)

Hint

Parametrization of the quagrangle (v1,v2,v3,v4) is :

(u,v)[0,1]×[0,1]v1+u(v2v1)+v(v4v1)uv(v2v1+v4v3).