From: asutton_at_[hidden]
Date: 2007-08-11 11:50:35
Author: asutton
Date: 2007-08-11 11:50:34 EDT (Sat, 11 Aug 2007)
New Revision: 38600
URL: http://svn.boost.org/trac/boost/changeset/38600
Log:
Added a matrix property map as an abstract property map over
other containers
Added:
sandbox/SOC/2007/graphs/boost/graph/matrix_property_map.hpp (contents, props changed)
Added: sandbox/SOC/2007/graphs/boost/graph/matrix_property_map.hpp
==============================================================================
--- (empty file)
+++ sandbox/SOC/2007/graphs/boost/graph/matrix_property_map.hpp 2007-08-11 11:50:34 EDT (Sat, 11 Aug 2007)
@@ -0,0 +1,67 @@
+// (C) Copyright Andrew Sutton 2007
+//
+// Use, modification and distribution are subject to the
+// Boost Software License, Version 1.0 (See accompanying file
+// LICENSE_1_0.txt or http://www.boost.org/LICENSE_1_0.txt)
+
+#ifndef BOOST_GRAPH_MATRIX_PROPERTY_MAP_HXX
+#define BOOST_GRAPH_MATRIX_PROPERTY_MAP_HXX
+
+#include <boost/graph/container_property_map.hpp>
+
+namespace boost
+{
+ // This property map is built specifically for property maps over
+ // matrices. Like the basic property map over a container, this builds
+ // the property abstraction over a matrix (usually a vector of vectors)
+ // and returns property maps over the nested containers.
+ template <typename Graph, typename Key, typename Matrix>
+ struct matrix_property_map
+ : boost::put_get_helper<
+ container_property_map<Graph, Key, typename Matrix::value_type>,
+ matrix_property_map<Graph, Key, Matrix> >
+ {
+ // abstract the indexing keys
+ typedef typename detail::choose_indexer<Graph, Key>::indexer_type indexer_type;
+
+ // aliases for the nested container and its corresponding map
+ typedef typename Matrix::value_type container_type;
+ typedef container_property_map<Graph, Key, container_type> map_type;
+
+ typedef Key key_type;
+
+ // This property map doesn't really provide access to nested containers,
+ // but returns property maps over them. Since property maps are all
+ // copy-constructible (or should be anyways), we never return references.
+ // As such, this property is only readable, but not writable. Curiously,
+ // the inner property map is actually an lvalue pmap.
+ typedef map_type value_type;
+ typedef map_type reference;
+ typedef readable_property_map_tag category;
+
+ matrix_property_map()
+ : m_matrix(0), m_graph(0)
+ { }
+
+ matrix_property_map(Matrix& m, const Graph& g)
+ : m_matrix(&m), m_graph(const_cast<Graph*>(&g))
+ { }
+
+ matrix_property_map(const matrix_property_map& x)
+ : m_matrix(x.m_matrix), m_graph(x.m_graph)
+ { }
+
+ inline reference operator [](key_type k) const
+ {
+ typedef typename indexer_type::value_type Index;
+ Index x = indexer_type::index(k, *m_graph);
+ return map_type((*m_matrix)[x], *m_graph);
+ }
+
+ private:
+ mutable Matrix* m_matrix;
+ mutable Graph* m_graph;
+ };
+}
+
+#endif