.TH "triangle" 6rheolef "Version 7.2" "rheolef" \" -*- nroff -*- .ad l .nh .SH NAME triangle \- reference element (rheolef-7\&.2) .PP .SH "DESCRIPTION" .PP The triangle \fBreference_element(6)\fP is \fCK = [0,1]\fP\&. .PP .nf K = { 0 < x0 < 1 and 0 < x1 < 1-x0 } x1 2 | + | + | + | + 0---------1 x0 .fi .PP This two-dimensional \fBreference_element(6)\fP is then transformed, after the Piola geometrical application, as a triangle in a 2D or 3D physical space, as a \fBgeo_element(6)\fP\&. .PP Curved high order transformed \fBgeo_element(6)\fP Pk triangle (k >= 1) are supported for 2D or 3D geometries\&. In these cases, the nodes of an high-order triangle are numbered as: .PP Note that high-order triangles have additional edge-nodes and face-nodes\&. These nodes are numbered as: first vertices, then edge-nodes, following the edge numbering order and orientation, and finally the face internal nodes, following the triangle lattice\&. .PP .nf 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 .fi .PP .SH "IMPLEMENTATION" .PP This documentation has been generated from file fem/geo_element/triangle\&.icc .PP .PP .nf 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][2] = { { 0, 1 }, { 1, 2 }, { 2, 0 } }; .fi .PP .SH AUTHOR Pierre Saramito .SH COPYRIGHT Copyright (C) 2000-2018 Pierre Saramito GPLv3+: GNU GPL version 3 or later . This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.