From 8ba0156d61b0e76ba47c256f6590d526bb9eb2b2 Mon Sep 17 00:00:00 2001
From: guido <guido@0785d39b-7218-0410-832d-ea1e28bc413d>
Date: Fri, 18 Feb 2000 22:10:26 +0000
Subject: [PATCH] laplacian added to interface

git-svn-id: https://svn.dealii.org/trunk@2442 0785d39b-7218-0410-832d-ea1e28bc413d
---
 deal.II/base/include/base/function.h | 26 +++++++++++++++
 deal.II/base/source/function.cc      | 49 ++++++++++++++++++++++++++++
 2 files changed, 75 insertions(+)

diff --git a/deal.II/base/include/base/function.h b/deal.II/base/include/base/function.h
index 277c0d1fde..f7e6829548 100644
--- a/deal.II/base/include/base/function.h
+++ b/deal.II/base/include/base/function.h
@@ -217,6 +217,32 @@ class Function : public FunctionTime,
     virtual void vector_gradient_list (const vector<Point<dim> >       &points,
 				       vector<vector<Tensor<1,dim> > > &gradients) const;
 
+				     /**
+				      * Compute the Laplacian of a given component at point #p#.
+				      */
+    virtual double laplacian (const Point<dim>   &p,
+			      const unsigned int  component = 0) const;
+
+				     /**
+				      * Compute the Laplacian of all components at point #p#
+				      * and store them in #values#.
+				      */
+    virtual void vector_laplacian (const Point<dim>   &p,
+				     Vector<double>     &values) const;
+    
+				     /**
+				      * Compute the Laplacian of one component at a set of points.
+				      */
+    virtual void laplacian_list (const vector<Point<dim> > &points,
+				 vector<double>            &values,
+				 const unsigned int         component = 0) const;
+
+				     /**
+				      * Compute the Laplacians of all components at a set of points.
+				      */
+    virtual void vector_laplacian_list (const vector<Point<dim> > &points,
+					vector<Vector<double> >   &values) const;
+
 				     /**
 				      * Exception
 				      */
diff --git a/deal.II/base/source/function.cc b/deal.II/base/source/function.cc
index 9d0da2c5c2..c689a7248c 100644
--- a/deal.II/base/source/function.cc
+++ b/deal.II/base/source/function.cc
@@ -306,6 +306,55 @@ void ConstantFunction<dim>::vector_value_list (const vector<Point<dim> > &points
 };
 
 
+template <int dim>
+double Function<dim>::laplacian (const Point<dim> &,
+			     const unsigned int) const
+{
+  Assert (false, ExcPureFunctionCalled());
+  return 0;
+}
+
+
+
+template <int dim>
+void Function<dim>::vector_laplacian (const Point<dim> &,
+				  Vector<double>   &) const
+{
+  Assert (false, ExcPureFunctionCalled());
+}
+
+
+
+template <int dim>
+void Function<dim>::laplacian_list (const vector<Point<dim> > &points,
+				vector<double>            &laplacians,
+				const unsigned int         component) const
+{
+				   // check whether component is in
+				   // the valid range is up to the
+				   // derived class
+  Assert (laplacians.size() == points.size(),
+	  ExcVectorHasWrongSize(laplacians.size(), points.size()));
+
+  for (unsigned int i=0; i<points.size(); ++i)
+    laplacians[i]  = this->laplacian (points[i], component);
+}
+
+
+
+template <int dim>
+void Function<dim>::vector_laplacian_list (const vector<Point<dim> > &points,
+				       vector<Vector<double> >   &laplacians) const
+{
+				   // check whether component is in
+				   // the valid range is up to the
+				   // derived class
+  Assert (laplacians.size() == points.size(),
+	  ExcVectorHasWrongSize(laplacians.size(), points.size()));
+
+  for (unsigned int i=0; i<points.size(); ++i)
+    this->vector_laplacian (points[i], laplacians[i]);
+}
 
 
 // explicit instantiations
-- 
2.39.5