From: Ralf Hartmann <Ralf.Hartmann@dlr.de>
Date: Wed, 22 Nov 2000 14:47:03 +0000 (+0000)
Subject: SparseMatrix<number>::n_actually_nonzero_elements () counts all entries that are... 
X-Git-Tag: v8.0.0~19936
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=aeddeac7b0d8f6e7598b66efba359a905eb4bae0;p=dealii.git

SparseMatrix<number>::n_actually_nonzero_elements () counts all entries that are really nonzero.


git-svn-id: https://svn.dealii.org/trunk@3496 0785d39b-7218-0410-832d-ea1e28bc413d
---

diff --git a/deal.II/lac/include/lac/sparse_matrix.h b/deal.II/lac/include/lac/sparse_matrix.h
index 3e59f49bab..57902399df 100644
--- a/deal.II/lac/include/lac/sparse_matrix.h
+++ b/deal.II/lac/include/lac/sparse_matrix.h
@@ -219,6 +219,20 @@ class SparseMatrix : public Subscriptor
 				      * be zero, it is counted anyway.
 				      */
     unsigned int n_nonzero_elements () const;
+
+				     /**
+				      * Return the number of actually
+				      * nonzero elements of this
+				      * matrix.
+				      *
+				      * Note, that this function does
+				      * (in contrary to the
+				      * @p{n_nonzero_elements}) NOT
+				      * count all entries of the
+				      * sparsity pattern but only the
+				      * ones that are nonzero.
+				      */
+    unsigned int n_actually_nonzero_elements () const;
     
 				     /**
 				      * Set the element @p{(i,j)} to @p{value}.
diff --git a/deal.II/lac/include/lac/sparse_matrix.templates.h b/deal.II/lac/include/lac/sparse_matrix.templates.h
index 40fbc14c59..1408679585 100644
--- a/deal.II/lac/include/lac/sparse_matrix.templates.h
+++ b/deal.II/lac/include/lac/sparse_matrix.templates.h
@@ -152,6 +152,16 @@ SparseMatrix<number>::n_nonzero_elements () const
 };
 
 
+template <typename number>
+unsigned int
+SparseMatrix<number>::n_actually_nonzero_elements () const
+{
+  Assert (cols != 0, ExcMatrixNotInitialized());
+  return count_if(&val[0], &val[n_nonzero_elements ()],
+		  bind2nd(not_equal_to<double>(), 0));
+};
+
+
 template <typename number>
 template <typename somenumber>
 SparseMatrix<number> &