Implement GetBoundarySizesAndTypesHEADsvnmaster

Provide aliased function GetBoundarySizesAndTypes that describes which
faces have what size and what type.


git-svn-id: http://svn.cactuscode.org/arrangements/CactusBase/CoordBase/trunk@53 0337457d-221f-4ee6-a5f0-14255d5370d8

1 files changed, 27 insertions, 0 deletions

diff --git a/doc/documentation.tex b/doc/documentation.tex
index 1f27685..020e6c3 100644
--- a/doc/documentation.tex
+++ b/doc/documentation.tex
@@ -603,6 +603,33 @@ periodicity, staggered boundary & no & yes & 0
 For other boundary conditions such as Dirichlet or Robin, one can
 choose these parameters freely.
 
+\section{Querying about boundary points}
+\label{CactusBase:CoordBase:boundary-query}
+
+When iterating over grid points, one usually needs to know about the
+boundary sizes and boundary types present. One convenient way is
+provided by the aliased function \texttt{GetBoundarySizesAndTypes}:
+\begin{verbatim}
+CCTK_INT FUNCTION GetBoundarySizesAndTypes
+  (CCTK_POINTER_TO_CONST IN cctkGH,
+   CCTK_INT IN size,
+   CCTK_INT OUT ARRAY bndsize,
+   CCTK_INT OUT ARRAY is_ghostbnd,
+   CCTK_INT OUT ARRAY is_symbnd,
+   CCTK_INT OUT ARRAY is_physbnd)
+\end{verbatim}
+The input argument \texttt{size} describes the size of the four output
+arrays as allocated by the caller, and should be \texttt{2*cctk\_dim}.
+The output of this routine describes, for each of the faces of the
+domain:
+\begin{description}
+\item[\texttt{bndsize}] The number of boundary points
+\item[\texttt{is\_ghostbnd}] Whether this face is a ghost
+  (inter-process) boundary
+\item[\texttt{is\_symbnd}] Whether this face is a symmetry boundary
+\item[\texttt{is\_physbnd}] Whether this face is a physical boundary
+\end{description}
+
 \section{Driver Issues}
 
 When using the CoordBase domain and boundary parameters, the driver