From 673d3c4f46a82f056f307e18a112e0b0b5aadd97 Mon Sep 17 00:00:00 2001 From: bangerth Date: Mon, 18 Sep 2006 17:19:52 +0000 Subject: [PATCH] Update a few comments git-svn-id: https://svn.dealii.org/trunk@13920 0785d39b-7218-0410-832d-ea1e28bc413d --- .../deal.II/include/dofs/dof_constraints.h | 24 ++++++++++++++++--- 1 file changed, 21 insertions(+), 3 deletions(-) diff --git a/deal.II/deal.II/include/dofs/dof_constraints.h b/deal.II/deal.II/include/dofs/dof_constraints.h index d6e4fc1ea6..2f7321cf65 100644 --- a/deal.II/deal.II/include/dofs/dof_constraints.h +++ b/deal.II/deal.II/include/dofs/dof_constraints.h @@ -212,7 +212,8 @@ class ConstraintMatrix : public Subscriptor * Add a new line to the * matrix. If the line already * exists, then the function - * simply returns. + * simply returns without doing + * anything. */ void add_line (const unsigned int line); @@ -247,7 +248,7 @@ class ConstraintMatrix : public Subscriptor * indices and values, to a line * of constraints. This function * is equivalent to calling the - * preceeding function more + * preceeding function * several times, but is faster. */ void add_entries (const unsigned int line, @@ -274,6 +275,23 @@ class ConstraintMatrix : public Subscriptor * are accepted. If the object * was already closed, then this * function returns immediately. + * + * This function also resolves + * chains of constraints. For + * example, degree of freedom 13 + * may be constrained to + * $u_{13}=u_3/2+u_7/2$ while + * degree of freedom 7 is itself + * constrained as + * $u_7=u_2/2+u_4/2$. Then, the + * resolution will be that + * $u_{13}=u_3/2+u_2/4+u_4/4$. Note, + * however, that cycles in this + * graph of constraints are not + * allowed, i.e. for example + * $u_4$ may not be constrained, + * directly or indirectly, to + * $u_{13}$ again. */ void close (); @@ -285,7 +303,7 @@ class ConstraintMatrix : public Subscriptor * this object. Both objects may * or may not be closed (by * having their function - * @p close called before), if + * @p close called before). If * this object was closed before, * then it will be closed * afterwards as well. Note, -- 2.39.5