<HTML> <!-- Copyright (c) Jeremy Siek 2001 Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) --> <Head> <Title>Edge Mutable Graph</Title> <BODY BGCOLOR="#ffffff" LINK="#0000ee" TEXT="#000000" VLINK="#551a8b" ALINK="#ff0000"> <IMG SRC="../../../boost.png" ALT="C++ Boost" width="277" height="86"> <BR Clear> <H2><A NAME="concept:EdgeMutableGraph"> Edge Mutable Graph </H2> The <I>Edge Mutable Graph</I> concept defines the interface for a graph that supports the addition and removal of edges. <H3>Refinement of</H3> <a href="./Graph.html">Graph</a> <H3>Associated Types</H3> No additional associated types. <h3>Valid Expressions</h3> <ul> <li><a name="sec:add_edge"><TT>add_edge(u, v, g)</TT></a> <b>returns</b> <TT>std::pair<edge_descriptor, bool></TT> <br><br> <b>Semantics:</b> Try to insert the edge <i>(u,v)</i> into the graph, returning the inserted edge or a parallel edge and a flag that specifies whether an edge was inserted. This operation must not invalidate vertex descriptors or vertex iterators of the graph, though it may invalidate edge descriptors or edge iterators.<br> <b>Preconditions:</b> <i>u</i> and <i>v</i> are vertices in the graph. <br> <b>Postconditions:</b> <i>(u,v)</i> is in the edge set of the graph. The returned edge descriptor will have <i>u</i> in the source position and <i>v</i> in the target position. If the graph allows parallel edges, then the returned flag is always <tt>true</tt>. If the graph does not allow parallel edges, if <i>(u,v)</i> was already in the graph then the returned flag is <tt>false</tt>. If <i>(u,v)</i> was not in the graph then the returned flag is <tt>true</tt>.<br> </li><br> <li><a name="sec:remove_edge_by_pair"><tt>remove_edge(u, v, g)</tt></a> <b>returns</b> <tt>void</tt><br><br> <b>Semantics:</b> Remove the edge <i>(u,v)</i> from the graph. If the graph allows parallel edges this removes all occurrences of <i>(u,v)</i>. <br> <b>Precondition:</b> <i>(u,v)</i> is in the edge set of the graph. <br> <b>Postcondition:</b> <i>(u,v)</i> is no longer in the edge set of the graph. <br> </li><br> <li> <a name="sec:remove_edge"><tt>remove_edge(e, g)</tt></a> <b>returns</b> <tt>void</tt><br><br> <b>Semantics:</b> Remove the edge <i>e</i> from the graph.<br> <b>Precondition:</b> <i>e</i> is an edge in the graph. <br> <b>Postcondition:</b> <i>e</i> is no longer in the edge set for <tt>g</tt>. <br> </li><br> <li> <a name="sec:clear_vertex"><tt>clear_vertex(u, g)</tt></a> <b>returns</b> <tt>void</tt><br><br> <b>Semantics:</b> Remove all edges to and from vertex <i>u</i> from the graph. <br> <b>Precondition:</b> <i>u</i> is a valid vertex descriptor of <tt>g</tt>. <br> <b>Postconditions:</b> <i>u</i> does not appear as a source or target of any edge in <tt>g</tt>. </li> </ul> <H3>Complexity guarantees</H3> <P> UNDER CONSTRUCTION <H3>See Also</H3> <a href="./graph_concepts.html">Graph concepts</a> <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> </BODY> </HTML>