From adf697a629a49fe36998d2c8838507b1f0617acb Mon Sep 17 00:00:00 2001 From: Wolfgang Bangerth Date: Sat, 5 Mar 2022 20:16:58 -0700 Subject: [PATCH] Minor doc adjustments. --- include/deal.II/base/quadrature_lib.h | 3 +++ include/deal.II/grid/reference_cell.h | 11 +++++++++-- 2 files changed, 12 insertions(+), 2 deletions(-) diff --git a/include/deal.II/base/quadrature_lib.h b/include/deal.II/base/quadrature_lib.h index 6832c428a1..d58afc17ec 100644 --- a/include/deal.II/base/quadrature_lib.h +++ b/include/deal.II/base/quadrature_lib.h @@ -588,6 +588,9 @@ public: * * No transformation is applied to the weights, and the weights referring to * points that live outside the reference simplex are simply discarded. + * Because this leads to (or *may* lead to) a sum of quadrature weights that + * do not equal the area of the simplex, the resulting quadrature formula + * is not useful for actually computing integrals. * * The main use of this quadrature formula is not to chop tensor product * quadratures. Ideally you should pass to this class a quadrature formula diff --git a/include/deal.II/grid/reference_cell.h b/include/deal.II/grid/reference_cell.h index 53beb6fb7b..8bc55b156a 100644 --- a/include/deal.II/grid/reference_cell.h +++ b/include/deal.II/grid/reference_cell.h @@ -205,9 +205,16 @@ public: /** * Return a quadrature rule with the support points of the given reference - * cell. + * cell. For 1d line segments, this corresponds to the quadrature points + * of the trapezoidal rule, which by taking tensor products easily + * generalizes also to other hypercube elements (see also QTrapezoid). + * For all reference cell shapes, the quadrature points are ordered + * in the same order as the vertices of the reference cell. * - * @note The weights of the quadrature object are left unfilled. + * @note The weights of the quadrature object are left unfilled and + * consequently the object cannot usefully be used for actually + * computing integrals. This is in contrast to, for example, the QTrapez + * class that correctly sets quadrature weights. */ template const Quadrature & -- 2.39.5