devn00b
/
EQ2EMu


			
				
					
						
						
							12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970717273747576777879
							<HTML>
<!--
     Copyright (c) Jeremy Siek, Lie-Quan Lee, and Andrew Lumsdaine 2000
    
     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>Boost Graph Library: opposite</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>

<H1><A NAME="sec:opposite"></A>
<TT>opposite</TT>
</H1>

<P>
<DIV ALIGN="left">
<TABLE CELLPADDING=3 border>

<TR><TH ALIGN="LEFT"><B>Complexity:</B></TH>
<TD ALIGN="LEFT"><i>O(1)</i>
</TD>
</TR>

<TR><TH ALIGN="LEFT"><B>Where Defined:</B></TH>
<TD ALIGN="LEFT">
<a href="../../../boost/graph/graph_utility.hpp"><TT>boost/graph/graph_utility.hpp</TT></a>
</TD>

</TABLE>
</DIV>

<P>
<PRE>
  template &lt;class Graph&gt;
  typename graph_traits&lt;Graph&gt;::vertex_descriptor
  opposite(typename graph_traits&lt;Graph&gt;::edge_descriptor e,
           typename graph_traits&lt;Graph&gt;::vertex_descriptor v,
           const Graph& g)
</pre>

Given an edge and a vertex which must be incident to the edge, this
function returns the opposite vertex. So if <tt>v</tt> is the source
vertex, this function returns the target vertex. If <tt>v</tt> is the
target, then this function returns the source vertex.

<h3>Example</h3>

<pre>
edge_descriptor e;
...
vertex_descriptor u, v;
boost::tie(u, v) = incident(e, g);
assert(v == opposite(e, u, g));
assert(u == opposite(e, v, g));
</pre>

<br>
<HR>
<TABLE>
<TR valign=top>
<TD nowrap>Copyright &copy; 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>)<br>
<A HREF="http://www.boost.org/people/liequan_lee.htm">Lie-Quan Lee</A>, Indiana University (<A HREF="mailto:llee@cs.indiana.edu">llee@cs.indiana.edu</A>)<br>
<A HREF="https://homes.cs.washington.edu/~al75">Andrew Lumsdaine</A>,
Indiana University (<A
HREF="mailto:lums@osl.iu.edu">lums@osl.iu.edu</A>)
</TD></TR></TABLE>

</BODY>
</HTML>