From ef5a0285d9bb097e120d52e8affb68b8a37048c9 Mon Sep 17 00:00:00 2001
From: brian <brian@0785d39b-7218-0410-832d-ea1e28bc413d>
Date: Mon, 2 Jun 2003 15:57:02 +0000
Subject: [PATCH] modified /= function.

git-svn-id: https://svn.dealii.org/trunk@7723 0785d39b-7218-0410-832d-ea1e28bc413d
---
 deal.II/lac/include/lac/block_sparse_matrix.h | 11 ++++++++++-
 deal.II/lac/include/lac/sparse_matrix.h       |  9 ++++++++-
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/deal.II/lac/include/lac/block_sparse_matrix.h b/deal.II/lac/include/lac/block_sparse_matrix.h
index 7bb1230478..7163f8c622 100644
--- a/deal.II/lac/include/lac/block_sparse_matrix.h
+++ b/deal.II/lac/include/lac/block_sparse_matrix.h
@@ -689,11 +689,17 @@ class BlockSparseMatrix : public Subscriptor
 				      * Exception
 				      */
     DeclException0 (ExcMatrixNotBlockSquare);
+
 				     /**
 				      * Exception
 				      */
     DeclException0 (ExcMatrixNotInitialized);
 
+				     /**
+				      * Exception
+				      */
+    DeclException0 (ExcDivideByZero);
+
     
   private:
 				     /**
@@ -1073,10 +1079,13 @@ BlockSparseMatrix<number>::operator /= (const number factor)
 {
   Assert (columns != 0, ExcMatrixNotInitialized());
   Assert (rows != 0, ExcMatrixNotInitialized());
+  Assert (factor !=0, ExcDivideByZero());
+
+  const number factor_inv = 1. / factor;
 
   for (unsigned int r=0; r<rows; ++r)
     for (unsigned int c=0; c<columns; ++c)
-      block(r,c) /= factor;
+      block(r,c) *= factor_inv;
 
   return *this;
 }
diff --git a/deal.II/lac/include/lac/sparse_matrix.h b/deal.II/lac/include/lac/sparse_matrix.h
index 8cfea37b48..29a393e557 100644
--- a/deal.II/lac/include/lac/sparse_matrix.h
+++ b/deal.II/lac/include/lac/sparse_matrix.h
@@ -1083,6 +1083,10 @@ class SparseMatrix : public virtual Subscriptor
 				     /**
 				      * Exception
 				      */
+    DeclException0 (ExcDivideByZero);
+				     /**
+				      * Exception
+				      */
     DeclException2 (ExcIteratorRange,
 		    int, int,
 		    << "The iterators denote a range of " << arg1
@@ -1290,12 +1294,15 @@ SparseMatrix<number>::operator /= (const number factor)
 {
   Assert (cols != 0, ExcMatrixNotInitialized());
   Assert (val != 0, ExcMatrixNotInitialized());
+  Assert (factor !=0, ExcDivideByZero());
+
+  const number factor_inv = 1. / factor;
 
   number             *val_ptr    = &val[0];
   const number *const end_ptr    = &val[cols->n_nonzero_elements()];
 
   while (val_ptr != end_ptr)
-    *val_ptr++ /= factor;
+    *val_ptr++ *= factor_inv;
 
   return *this;
 }
-- 
2.39.5