From: Peter Munch <peterrmuench@gmail.com>
Date: Sat, 5 Dec 2020 12:10:38 +0000 (+0100)
Subject: Add QGaussPyramid
X-Git-Tag: v9.3.0-rc1~776^2
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=93260d538797dc3d4e4bb69f228e9ea74a17b0ff;p=dealii.git

Add QGaussPyramid
---

diff --git a/include/deal.II/simplex/quadrature_lib.h b/include/deal.II/simplex/quadrature_lib.h
index 09037ff897..7962091ca5 100644
--- a/include/deal.II/simplex/quadrature_lib.h
+++ b/include/deal.II/simplex/quadrature_lib.h
@@ -66,6 +66,21 @@ namespace Simplex
     explicit QGaussWedge(const unsigned int n_points_1D);
   };
 
+  /**
+   * Integration rule for pyramid entities.
+   */
+  template <int dim>
+  class QGaussPyramid : public Quadrature<dim>
+  {
+  public:
+    /**
+     * Users specify a number `n_points_1D` as an indication of what polynomial
+     * degree to be integrated exactly. For details, see the comments of
+     * Simplex::QGauss.
+     */
+    explicit QGaussPyramid(const unsigned int n_points_1D);
+  };
+
 } // namespace Simplex
 
 DEAL_II_NAMESPACE_CLOSE
diff --git a/source/simplex/quadrature_lib.cc b/source/simplex/quadrature_lib.cc
index 277633a373..5d3ea4df22 100644
--- a/source/simplex/quadrature_lib.cc
+++ b/source/simplex/quadrature_lib.cc
@@ -168,6 +168,50 @@ namespace Simplex
            ExcMessage("No valid quadrature points!"));
   }
 
+
+
+  template <int dim>
+  QGaussPyramid<dim>::QGaussPyramid(const unsigned int n_points_1D)
+    : Quadrature<dim>()
+  {
+    AssertDimension(dim, 3);
+
+    if (n_points_1D == 1)
+      {
+        const double Q14 = 1.0 / 4.0;
+        const double Q43 = 4.0 / 3.0;
+
+        this->quadrature_points.emplace_back(0, 0, Q14);
+        this->weights.emplace_back(Q43);
+      }
+    else if (n_points_1D == 2)
+      {
+        // clang-format off
+        this->quadrature_points.emplace_back(-0.26318405556971, -0.26318405556971, 0.54415184401122);
+        this->quadrature_points.emplace_back(-0.50661630334979, -0.50661630334979, 0.12251482265544);
+        this->quadrature_points.emplace_back(-0.26318405556971, +0.26318405556971, 0.54415184401122);
+        this->quadrature_points.emplace_back(-0.50661630334979, +0.50661630334979, 0.12251482265544);
+        this->quadrature_points.emplace_back(+0.26318405556971, -0.26318405556971, 0.54415184401122);
+        this->quadrature_points.emplace_back(+0.50661630334979, -0.50661630334979, 0.12251482265544);
+        this->quadrature_points.emplace_back(+0.26318405556971, +0.26318405556971, 0.54415184401122);
+        this->quadrature_points.emplace_back(+0.50661630334979, +0.50661630334979, 0.12251482265544);
+        // clang-format on
+
+        this->weights.emplace_back(0.10078588207983);
+        this->weights.emplace_back(0.23254745125351);
+        this->weights.emplace_back(0.10078588207983);
+        this->weights.emplace_back(0.23254745125351);
+        this->weights.emplace_back(0.10078588207983);
+        this->weights.emplace_back(0.23254745125351);
+        this->weights.emplace_back(0.10078588207983);
+        this->weights.emplace_back(0.23254745125351);
+      }
+
+    AssertDimension(this->quadrature_points.size(), this->weights.size());
+    Assert(this->quadrature_points.size() > 0,
+           ExcMessage("No valid quadrature points!"));
+  }
+
 } // namespace Simplex
 
 
@@ -177,5 +221,8 @@ template class Simplex::QGauss<3>;
 template class Simplex::QGaussWedge<1>;
 template class Simplex::QGaussWedge<2>;
 template class Simplex::QGaussWedge<3>;
+template class Simplex::QGaussPyramid<1>;
+template class Simplex::QGaussPyramid<2>;
+template class Simplex::QGaussPyramid<3>;
 
 DEAL_II_NAMESPACE_CLOSE