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| <Head> |
| <Title>Boost Graph Library: Transpose Graph</Title> |
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| |
| <H1><TT>transpose_graph</TT></H1> |
| |
| <PRE> |
| template <class <a href="./VertexListGraph.html">VertexListGraph</a>, class <a href="./MutableGraph.html">MutableGraph</a>> |
| void transpose_graph(const VertexListGraph& G, MutableGraph& G_T, |
| const bgl_named_params<P, T, R>& params = <i>all defaults</i>) |
| </PRE> |
| |
| <P> |
| This function computes the transpose of a directed graph. The |
| transpose of a directed graph <i>G = (V, E)</i>is the graph |
| <i>G<sup>T</sup> = (V, E<sup>T</sup>)</i> , where <i>E<sup>T</sup> = |
| {(v, u) in V x V: (u, v) in E}</i> . i.e., <i>G<sup>T</sup></i> is |
| <i>G</i> with all its edges reversed. Graph <TT>G_T</TT> passed into |
| the algorithm must have no vertices and |
| no edges. The vertices and edges will be added by <tt>transpose_graph()</tt> by |
| calling <tt>add_vertex</tt> and <tt>add_edge</tt> as follows for each edge |
| <i>(u,v)</i> in <tt>G</tt>. |
| |
| <H3>Example</H3> |
| |
| Here's an example of transposing a graph: |
| <a href="../example/transpose-example.cpp"><tt>example/transpose-example.cpp</tt></a>. |
| |
| <H3>Where Defined</H3> |
| |
| <P> |
| <a href="../../../boost/graph/transpose_graph.hpp"><TT>boost/graph/transpose_graph.hpp</TT></a> |
| |
| <P> |
| |
| <H3>Parameters</H3> |
| |
| IN: <tt>const VertexListGraph& G</tt> |
| <blockquote> |
| A directed graph. The graph type must be a model of <a href="./VertexListGraph.html">Vertex List Graph</a>. |
| </blockquote> |
| |
| OUT: <tt>const MutableGraph& G_T</tt> |
| <blockquote> |
| The transposed graph. The graph type must be a model of <a |
| href="./MutableGraph.html">Mutable Graph</a>. |
| </blockquote> |
| |
| <h3>Named Parameters</h3> |
| |
| IN: <tt>vertex_copy(VertexCopier vc)</tt> |
| <blockquote> |
| This is a <a href="http://www.sgi.com/tech/stl/BinaryFunction.html">Binary Function</a> that copies the properties of a vertex in the original graph |
| into the corresponding vertex in the copy.<br> |
| |
| <b>Default:</b> <tt>vertex_copier<VertexListGraph, MutableGraph></tt> |
| which uses the property tag <tt>vertex_all</tt> to access a property |
| map from the graph. |
| </blockquote> |
| |
| IN: <tt>edge_copy(EdgeCopier ec)</tt> |
| <blockquote> |
| This is a <a href="http://www.sgi.com/tech/stl/BinaryFunction.html">Binary Function</a> that copies the properties of an edge in the original graph |
| into the corresponding edge in the copy.<br> |
| |
| <b>Default:</b> <tt>edge_copier<VertexListGraph, MutableGraph></tt> |
| which uses the property tag <tt>edge_all</tt> to access a property |
| map from the graph. |
| </blockquote> |
| |
| IN: <tt>vertex_index_map(VertexIndexMap i_map)</tt> |
| <blockquote> |
| The vertex index map type must be a model of <a |
| href="../../property_map/doc/ReadablePropertyMap.html">Readable Property |
| Map</a> and must map the vertex descriptors of <tt>G</tt> to the |
| integers from 0 to <tt>num_vertices(G)</tt>.<br> |
| |
| <b>Default:</b> <tt>get(vertex_index, G)</tt> |
| Note: if you use this default, make sure your graph has |
| an internal <tt>vertex_index</tt> property. For example, |
| <tt>adjacenty_list</tt> with <tt>VertexList=listS</tt> does |
| not have an internal <tt>vertex_index</tt> property. |
| </blockquote> |
| |
| |
| UTIL/OUT: <tt>orig_to_copy(Orig2CopyMap c)</tt> |
| <blockquote> |
| This maps vertices in the original graph to vertices in the copy. |
| |
| <b>Default:</b> an <a |
| href="../../property_map/doc/iterator_property_map.html"> |
| </tt>iterator_property_map</tt></a> created from a |
| <tt>std::vector</tt> of the output graph's vertex descriptor type of size |
| <tt>num_vertices(g)</tt> and using the <tt>i_map</tt> for the index |
| map. |
| </blockquote> |
| |
| <H3>Complexity</H3> |
| |
| <P> |
| The time complexity is <i>O(V + E)</i>. |
| |
| |
| |
| <br> |
| <HR> |
| <TABLE> |
| <TR valign=top> |
| <TD nowrap>Copyright © 2000-2001</TD><TD> |
| <A HREF="http://www.boost.org/people/jeremy_siek.htm">Jeremy Siek</A>, Indiana University (<A HREF="mailto:jsiek@osl.iu.edu">jsiek@osl.iu.edu</A>) |
| </TD></TR></TABLE> |
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