added doxygen documentation and changelog entry for gauss-radau rules

CHANGELOG.md

@@ -12,6 +12,10 @@
   but this was never enforced.  Starting with version 2.8, compilation
   fails with an error message if this constructor is used with `dim!=coorddim`.
 
+- Two new sets of quadrature rules are provided: the left and right Gauss-Radau quadrature rules.
+  These are optimal rules that include only one endpoint of the integration interval
+  (either left or right) and integrate polynomials of order 2n - 2 exactly.
+
 ## Deprecations and removals
 
 - Remove code needed to use reference elements by reference.

dune/geometry/quadraturerules.hh

@@ -80,7 +80,9 @@ namespace Dune {
     enum Enum {
       /** \brief Gauss-Legendre rules (default)
       *
-      *  -1D: Gauss-Jacobi rule with parameters \f$\alpha = \beta =0 \f$
+      *  -1D: Gauss-Jacobi rule with parameters \f$\alpha = \beta =0 \f$, i.e. for integrals with a constant weight function.
+      *       The quadrature points do not include interval endpoints.
+      *       Polynomials of order 2n - 1 can be integrated exactly.
       *  -higher dimension: For the 2D/3D case efficient rules for certain geometries may be used if available.
       *                     Higher dimensional quadrature rules are constructed via \p TensorProductQuadratureRule.
       *                     In this case the 1D rules eventually need higher order to compensate occuring weight functions(i.e. simplices).
@@ -101,7 +103,7 @@ namespace Dune {
       */
       GaussJacobi_2_0 = 2,
 
-      /** \brief Gauss-Legendre rules with \f$\alpha =n\f$.
+      /** \brief Gauss-Legendre rules with \f$\alpha =n\f$
       *
       *  -1D: Gauss-Jacobi rule with parameters \f$\alpha = n,\ \beta =0 \f$
       *  -higher dimension: For the 2D/3D case efficient rules for certain geometries may be used if available.
@@ -113,8 +115,30 @@ namespace Dune {
       *   \note For details please use the book "Approximate Calculation of Multiple Integrals" by A.H. Stroud published in 1971.
       */
       GaussJacobi_n_0 = 3,
+
+      /** \brief Gauss-Lobatto rules
+       *
+       * 1D: Gauss-Lobatto rules for a constant weight function.
+       * These are optimal rules under the constraint that both interval endpoints are quadrature points.
+       * Polynomials of order 2n - 3 can be integrated exactly.
+       */
       GaussLobatto = 4,
+
+      /** \brief Gauss-Radau rules including the left endpoint
+       *
+       * 1D: Gauss-Radau rules for a constant weight function.
+       * These are optimal rules under the constraint that the left endpoint of the integration interval is a quadrature point.
+       * Polynomials of order 2n - 2 can be integrated exactly.
+       */
       GaussRadauLeft = 5,
+
+      /** \brief Gauss-Radau rules including the right endpoint
+       *
+       * 1D: Gauss-Radau rules for a constant weight function.
+       * These are optimal rules under the constraint that the right endpoint of the integration interval is a quadrature point.
+       * Polynomials of order 2n - 2 can be integrated exactly.
+       * The right Gauss-Radau rules are the just the mirrored left Gauss-Radau rules.
+       */
       GaussRadauRight = 6,
       size
     };