SIMPLE SOLUTIONS

# TRIANGLE(7RHEOLEF) - Linux man page online | Overview, conventions, and miscellany

Triangle reference element.

Chapter
rheolef-6.7
triangle(7rheolef) rheolef-6.7 triangle(7rheolef)

## NAME

triangle - Triangle reference element

## DESCRIPTION

The triangle reference element is K = { 0 < x < 1 and 0 < y < 1-x }

## NUMBERING

y 2 | + | + | + | + 0---------1 x Curved high order Pk triangles (k >= 1), in 2d or 3d geometries, are supported. These triangles have additional edge-nodes and face-nodes.

## THESE NODES ARE NUMBERED AS

first vertex, then edge-node, following the edge numbering order and orientation, and finally the face internal nodes, following the triangle lattice. See below for edge num‐ bering and orientation. 2 2 2 | + | + | + | + 7 6 9 8 5 4 | + 10 14 7 | + 8 9 5 11 12 13 6 | + | + | + 0-----3-----1 0---3---4---1 0--3--4--5--1 P2 P3 P4

## IMPLEMENTATION

const size_t dimension = 2; const Float measure = 0.5; const size_t n_vertex = 3; const point vertex [n_vertex] = { point(0, 0), point(1, 0), point(0, 1) }; const size_t n_edge = 3; const size_t edge [n_edge] = { { 0, 1 }, { 1, 2 }, { 2, 0 } };
rheolef-6.7 rheolef-6.7 triangle(7rheolef)