From: Wolfgang Bangerth <bangerth@math.tamu.edu>
Date: Fri, 14 Apr 2000 16:23:33 +0000 (+0000)
Subject: Allow matrices to be empty upon check of equality.
X-Git-Tag: v8.0.0~20668
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9a09c5f385aea2d8fc50ed4da765c05b333f8278;p=dealii.git

Allow matrices to be empty upon check of equality.


git-svn-id: https://svn.dealii.org/trunk@2727 0785d39b-7218-0410-832d-ea1e28bc413d
---

diff --git a/deal.II/lac/include/lac/full_matrix.templates.h b/deal.II/lac/include/lac/full_matrix.templates.h
index d73fa76fe4..469c7a65d6 100644
--- a/deal.II/lac/include/lac/full_matrix.templates.h
+++ b/deal.II/lac/include/lac/full_matrix.templates.h
@@ -1075,13 +1075,15 @@ template <typename number>
 bool
 FullMatrix<number>::operator == (const FullMatrix<number> &m) const
 {
-  Assert (val != 0, ExcEmptyMatrix());
-  
-  bool q = (dim_range==m.dim_range) && (dim_image==m.dim_image);
-  if (!q) return false;
-
-  return equal (&val[0], &val[dim_range*dim_image],
-		&m.val[0]);
+				   // the matrices may either be both
+				   // empty, or of same size and with
+				   // same values, if they shall be
+				   // equal
+  return ( ((val==0) && (m.val==0)) ||
+	   ((dim_range==m.dim_range) &&
+	    (dim_image==m.dim_image) &&
+	    equal (&val[0], &val[dim_range*dim_image],
+		   &m.val[0])));
 };