From: wolf <wolf@0785d39b-7218-0410-832d-ea1e28bc413d>
Date: Tue, 1 Feb 2000 17:57:28 +0000 (+0000)
Subject: Add a function which we can ask whether a certain DoF is constrained
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b9b205024c693e64e8f16e293bd76eadb4c9ab4e;p=dealii-svn.git

Add a function which we can ask whether a certain DoF is constrained
or not.


git-svn-id: https://svn.dealii.org/trunk@2308 0785d39b-7218-0410-832d-ea1e28bc413d
---

diff --git a/deal.II/deal.II/include/dofs/dof_constraints.h b/deal.II/deal.II/include/dofs/dof_constraints.h
index 4b4500ed1b..740cb20431 100644
--- a/deal.II/deal.II/include/dofs/dof_constraints.h
+++ b/deal.II/deal.II/include/dofs/dof_constraints.h
@@ -154,6 +154,24 @@ class ConstraintMatrix : public Subscriptor
 				      */
     unsigned int n_constraints () const;
 
+				     /**
+				      * Return whether the degree of
+				      * freedom with number #index# is
+				      * a constrained one.
+				      *
+				      * Note that if #close# was
+				      * called before, then this
+				      * function is significantly
+				      * faster, since then the
+				      * constrained degrees of freedom
+				      * are sorted and we can do a
+				      * binary search, while before
+				      * #close# was called, we have to
+				      * perform a linear search
+				      * through all entries.
+				      */
+    bool is_constrained (const unsigned int index) const;
+    
 				     /**
 				      * Condense a given sparsity pattern. This
 				      * function assumes the uncondensed
diff --git a/deal.II/deal.II/source/dofs/dof_constraints.cc b/deal.II/deal.II/source/dofs/dof_constraints.cc
index b07515369a..9e1cf51df2 100644
--- a/deal.II/deal.II/source/dofs/dof_constraints.cc
+++ b/deal.II/deal.II/source/dofs/dof_constraints.cc
@@ -12,7 +12,9 @@
 
 
 
-bool ConstraintMatrix::ConstraintLine::operator < (const ConstraintMatrix::ConstraintLine &a) const
+inline
+bool
+ConstraintMatrix::ConstraintLine::operator < (const ConstraintLine &a) const
 {
   return line < a.line;
 };
@@ -308,12 +310,38 @@ void ConstraintMatrix::condense (SparsityPattern &sparsity) const {
 
 
 
-unsigned int ConstraintMatrix::n_constraints () const {
+unsigned int ConstraintMatrix::n_constraints () const
+{
   return lines.size();
 };
 
 
 
+bool ConstraintMatrix::is_constrained (const unsigned int index) const 
+{
+  if (sorted == true)
+    {
+      
+      ConstraintLine index_comparison;
+      index_comparison.line = index;
+      
+      return binary_search (lines.begin (),
+			    lines.end (),
+			    index_comparison);
+    }
+  else
+    {
+      for (vector<ConstraintLine>::const_iterator i=lines.begin();
+	   i!=lines.end(); ++i)
+	if (i->line == index)
+	  return true;
+
+      return false;
+    };
+};
+
+
+
 void ConstraintMatrix::print (ostream &out) const {
   for (unsigned int i=0; i!=lines.size(); ++i)
     for (unsigned int j=0; j!=lines[i].entries.size(); ++j)