Element local coordinates and numbering.
This modules allows for a consistent local numbering scheme throughout pyFormex. When interfacing with other programs, one should be aware that conversions may be necessary. Conversions to/from external programs should be done by the interface modules.
Element base class: an empty element.
All derived classes should have a capitalized name: starting with an uppercase character and further only lower case and digits.
Each element is defined by the following attributes: vertices: the natural coordinates of its vertices, edges: a list of edges, each defined by a couple of node numbers, faces: a list of faces, each defined by a list of minimum 3 node numbers, element: a list of all node numbers
The vertices of the elements are defined in a unit space [0,1] in each axis direction.
The elements guarantee a fixed local numbering scheme of the vertices. One should however not rely on a specific numbering scheme of edges, faces or elements. For solid elements, it is guaranteed that the vertices of all faces are numbered in a consecutive order spinning positively around the outward normal on the face.
Element objects have the following methods:
A 3-node triangle
Tri3 objects have the following methods:
A 4-node quadrilateral
Quad4 objects have the following methods:
A 4-node quadrilateral
Quad9 objects have the following methods:
A 4-node tetrahedron
Tet4 objects have the following methods:
A 6-node wedge element
Wedge6 objects have the following methods:
An 8-node hexahedron
Hex8 objects have the following methods:
An icosahedron: a regular polyhedron with 20 triangular surfaces.
nfaces = 20, nedges = 30, nvertices = 12
Icosa objects have the following methods: