quadrilateral_witherden_rule

quadrilateral_witherden_rule, a C code which returns a Witherden quadrature rule, with exactness up to total degree 21, over the interior of a quadrilateral.

The unit quadrilateral has vertices (0,0), (1,0), (1,1), (0,1).

Licensing:

The information on this web page is distributed under the MIT license.

Languages:

quadrilateral_witherden_rule is available in a C version and a C++ version and a Fortran90 version and a MATLAB version and an Octave version and a Python version.

Related Data and Programs:

quadrilateral_witherden_rule_test

c_rule, a C code which computes a quadrature rule which estimates the integral of a function f(x), which might be defined over a one dimensional region (a line) or more complex shapes such as a circle, a triangle, a quadrilateral, a polygon, or a higher dimensional region, and which might include an associated weight function w(x).

Reference:

1. Freddie Witherden, Peter Vincent,
   On the identification of symmetric quadrature rules for finite element methods,
   Computers and Mathematics with Applications,
   Volume 69, pages 1232-1241, 2015.

Source Code:

• quadrilateral_witherden_rule.c, the source code.
• quadrilateral_witherden_rule.h, the include file.
• quadrilateral_witherden_rule.sh, compiles the source code.

• quadrilateral_witherden_rule_to_c.m, a MATLAB script which reads a data file describing one of the rules and writes a C function to return points and weights.