iterator_property_map<RandomAccessIterator, OffsetMap, T, R>
This property map is an adaptor that converts any random access iterator into a Lvalue Property Map. The OffsetMap type is responsible for converting key objects to integers that can be used as offsets with the random access iterator.
// print out the capacity and flow for all the edges in the graph
template <class Graph, class CapacityPMap, class FlowPMap>
void print_network(Graph& G, CapacityPMap capacity, FlowPMap flow)
{
typedef typename boost::graph_traits<Graph>::vertex_iterator Viter;
typedef typename boost::graph_traits<Graph>::out_edge_iterator OutEdgeIter;
typedef typename boost::graph_traits<Graph>::in_edge_iterator InEdgeIter;
Viter ui, uiend;
for (boost::tie(ui, uiend) = vertices(G); ui != uiend; ++ui) {
OutEdgeIter out, out_end;
std::cout << *ui << "\t";
for(boost::tie(out, out_end) = out_edges(*ui, G); out != out_end; ++out)
std::cout << "--(" << get(capacity, *out) << ", "
<< get(flow, *out) << ")--> " << target(*out,G) << "\t";
std::cout << std::endl << "\t";
InEdgeIter in, in_end;
for(boost::tie(in, in_end) = in_edges(*ui, G); in != in_end; ++in)
std::cout << "<--(" << get(capacity, *in) << "," << get(flow, *in) << ")-- "
<< source(*in,G) << "\t";
std::cout << std::endl;
}
}
int main(int, char*[])
{
typedef boost::adjacency_list<boost::vecS, boost::vecS,
boost::bidirectionalS, boost::no_plugin,
boost::plugin<boost::id_tag, std::size_t> > Graph;
const int num_vertices = 9;
Graph G(num_vertices);
int capacity[] = { 10, 20, 20, 20, 40, 40, 20, 20, 20, 10 };
int flow[] = { 8, 12, 12, 12, 12, 12, 16, 16, 16, 8 };
// add edges to the graph, and assign each edge an ID number
// to index into the property arrays
add_edge(G, 0, 1, 0);
// ...
typedef boost::graph_traits<Graph>::edge_descriptor Edge;
typedef boost::property_map<Graph, boost::id_tag>::type EdgeID_PMap;
EdgeID_PMap edge_id = get(boost::edge_index(), G);
boost::iterator_property_map<int*, EdgeID_PMap, int, int&>
capacity_pa(capacity, edge_id),
flow_pa(flow, edge_id);
print_network(G, capacity_pa, flow_pa);
return 0;
}
boost/property_map/property_map.hpp
| Parameter | Description | Default |
|---|---|---|
| Iterator | Must be a model of Random Access Iterator. | |
| OffsetMap | Must be a model of Readable Property Map and the value type must be convertible to the difference type of the iterator. | |
| T | The value type of the iterator. | std::iterator_traits<RandomAccessIterator>::value_type |
| R | The reference type of the iterator. | std::iterator_traits<RandomAccessIterator>::reference |
In addition to the methods and functions required by Lvalue Property Map, this class has the following members.
property_traits<iterator_property_map>::value_typeThis is the same type as std::iterator_traits<Iterator>::value_type.
iterator_property_map(Iterator i)Constructor. The OffsetMap is default constructed.
iterator_property_map(Iterator i, OffsetMap m)Constructor.
reference operator[](const key_type& v) constThe operator bracket for property access. The reference is from std::iterator_traits<Iterator> and the key_type is from boost::property_traits<OffsetMap>.
template <class RAIter, class OffsetMap>
iterator_property_map<RAIter, OffsetMap,
typename std::iterator_traits<RAIter>::value_type,
typename std::iterator_traits<RAIter>::reference
>
make_iterator_property_map(RAIter iter, OffsetMap omap)
A function for conveniently creating an iterator map.
template <class RAIter, class OffsetMap, class ValueType>
iterator_property_map<RAIter, OffsetMap,
typename std::iterator_traits<RAIter>::value_type,
typename std::iterator_traits<RAIter>::reference
>
make_iterator_property_map(RAIter iter, OffsetMap omap, ValueType dummy_arg)
Use this function instead of the 2-argument version if
your compiler does not support partial specialization
(like Visual C++).
| Copyright © 2000-2002 |
Jeremy Siek,
Univ.of Notre Dame (jsiek@osl.iu.edu) Lie-Quan Lee, Univ.of Notre Dame (llee1@osl.iu.edu) Andrew Lumsdaine, Univ.of Notre Dame (lums@osl.iu.edu) |