From: Wolfgang Bangerth <bangerth@math.tamu.edu>
Date: Thu, 27 Sep 2001 13:11:12 +0000 (+0000)
Subject: Templatize the scalar product between vectors on the underlying types. This allows... 
X-Git-Tag: v8.0.0~18706
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b95605e83fd68333a53134186a1d4776b52512fa;p=dealii.git

Templatize the scalar product between vectors on the underlying types. This allows scalar products between vectors of float and double, etc.


git-svn-id: https://svn.dealii.org/trunk@5110 0785d39b-7218-0410-832d-ea1e28bc413d
---

diff --git a/deal.II/lac/include/lac/vector.h b/deal.II/lac/include/lac/vector.h
index 7533548e7d..bc5305d9b0 100644
--- a/deal.II/lac/include/lac/vector.h
+++ b/deal.II/lac/include/lac/vector.h
@@ -203,9 +203,18 @@ class Vector
     Vector<Number> & operator= (const Vector<Number2>& V);
     
 				     /**
-				      * $U = U * V$: scalar product.
+				      * Return the scalar product of
+				      * two vectors.  The return type
+				      * is the underlying type of
+				      * @p{this} vector, so the return
+				      * type and the accuracy with
+				      * which it the result is
+				      * computed depend on the order
+				      * of the arguments of this
+				      * vector.
 				      */
-    Number operator* (const Vector<Number>& V) const;
+    template <typename Number2>
+    Number operator* (const Vector<Number2> &V) const;
 
 				     /**
 				      * Return square of the $l_2$-norm.
diff --git a/deal.II/lac/include/lac/vector.templates.h b/deal.II/lac/include/lac/vector.templates.h
index 3ce808a5ba..842fdf818f 100644
--- a/deal.II/lac/include/lac/vector.templates.h
+++ b/deal.II/lac/include/lac/vector.templates.h
@@ -104,14 +104,15 @@ bool Vector<Number>::all_zero () const
 
 
 template <typename Number>
-Number Vector<Number>::operator * (const Vector<Number>& v) const
+template <typename Number2>
+Number Vector<Number>::operator * (const Vector<Number2>& v) const
 {
   Assert (dim!=0, ExcEmptyVector());
-
-  if (&v == this)
+  
+  if (this == reinterpret_cast<const Vector<Number>*>(&v))
     return norm_sqr();
   
-  Assert (dim == v.dim, ExcDimensionMismatch(dim, v.dim));
+  Assert (dim == v.size(), ExcDimensionMismatch(dim, v.size()));
   
   Number sum0 = 0,
 	 sum1 = 0,
@@ -122,8 +123,8 @@ Number Vector<Number>::operator * (const Vector<Number>& v) const
 				   // allowing pipelined commands to be
 				   // executed in parallel
   const_iterator ptr  = begin(),
-		 vptr = v.begin(),
 		 eptr = ptr + (dim/4)*4;
+  typename Vector<Number2>::const_iterator vptr = v.begin();
   while (ptr!=eptr)
     {
       sum0 += (*ptr++ * *vptr++);
diff --git a/deal.II/lac/source/vector.cc b/deal.II/lac/source/vector.cc
index 2ff0e2217f..d007108eeb 100644
--- a/deal.II/lac/source/vector.cc
+++ b/deal.II/lac/source/vector.cc
@@ -17,9 +17,13 @@
 // explicit instantiations
 template class Vector<double>;
 template Vector<double>& Vector<double>::operator=(const Vector<float>&);
+template double Vector<double>::operator*(const Vector<float>&) const;
+template double Vector<double>::operator*(const Vector<double>&) const;
 
 template class Vector<float>;
 template Vector<float>& Vector<float>::operator=(const Vector<double>&);
+template float Vector<float>::operator*(const Vector<float>&) const;
+template float Vector<float>::operator*(const Vector<double>&) const;
 
 // see the .h file for why these functions are disabled.
 // template Vector<float>::Vector (const Vector<double>& v);
diff --git a/deal.II/lac/source/vector.long_double.cc b/deal.II/lac/source/vector.long_double.cc
index 86b8d00969..e8a7d17ee3 100644
--- a/deal.II/lac/source/vector.long_double.cc
+++ b/deal.II/lac/source/vector.long_double.cc
@@ -16,10 +16,16 @@
 
 // explicit instantiations
 template class Vector<long double>;
+
 template Vector<long double>& Vector<long double>::operator=(const Vector<float>&);
 template Vector<long double>& Vector<long double>::operator=(const Vector<double>&);
 template Vector<double>& Vector<double>::operator=(const Vector<long double>&);
 template Vector<float>& Vector<float>::operator=(const Vector<long double>&);
+
+template float Vector<float>::operator * (const Vector<long double> &) const;
+template double Vector<double>::operator * (const Vector<long double> &) const;
+template long double Vector<long double>::operator * (const Vector<float> &) const;
+template long double Vector<long double>::operator * (const Vector<double> &) const;
 // see the .h file for why these functions are disabled.
 // template Vector<float>::Vector (const Vector<double>& v);
 // template Vector<double>::Vector (const Vector<float>& v);