Finite Element Analysis Toolbox
QUADRULE Calculate numerical quadrature/integration rules.
[ X, W, N ] = QUADRULE( N0, N_SDIM, N_PCELL ) Computes numerical quadrature integration rules for the appropriate grid cell type determined by the space dimension N_SDIM and the number of points/vertices per cell N_PCELL. N0 specifies the desired order and degree of the rule. Returns evaluation coordinates in X (Barycentric for lines and simplices, and reference coordinates for quadilaterals and hexahedra), weights in W, and the total number of integration points in N.
Tabulated Gauss quadrature rules are used for triangles and tetrahedra with N0 <= 5, while for the rest open Gauss-Legendre multidimensional (and collapsed) quadrature is used. Note that the 3rd degree/order triangle and tetrahedral rule include negative weights.