Du kannst nicht mehr als 25 Themen auswählen
Themen müssen entweder mit einem Buchstaben oder einer Ziffer beginnen. Sie können Bindestriche („-“) enthalten und bis zu 35 Zeichen lang sein.
312 Zeilen
14 KiB
HTML
312 Zeilen
14 KiB
HTML
vor 8 Jahren
|
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
|
||
|
|
<!-- NewPage -->
|
||
|
|
<html lang="en">
|
||
|
|
<head>
|
||
|
|
<!-- Generated by javadoc (version 1.7.0_79) on Sun Apr 03 00:28:30 PDT 2016 -->
|
||
|
|
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
|
||
|
|
<title>VertexCovers (JGraphT : a free Java graph library)</title>
|
||
|
|
<meta name="date" content="2016-04-03">
|
||
|
|
<link rel="stylesheet" type="text/css" href="../../../stylesheet.css" title="Style">
|
||
|
|
</head>
|
||
|
|
<body>
|
||
|
|
<script type="text/javascript"><!--
|
||
|
|
if (location.href.indexOf('is-external=true') == -1) {
|
||
|
|
parent.document.title="VertexCovers (JGraphT : a free Java graph library)";
|
||
|
|
}
|
||
|
|
//-->
|
||
|
|
</script>
|
||
|
|
<noscript>
|
||
|
|
<div>JavaScript is disabled on your browser.</div>
|
||
|
|
</noscript>
|
||
|
|
<!-- ========= START OF TOP NAVBAR ======= -->
|
||
|
|
<div class="topNav"><a name="navbar_top">
|
||
|
|
<!-- -->
|
||
|
|
</a><a href="#skip-navbar_top" title="Skip navigation links"></a><a name="navbar_top_firstrow">
|
||
|
|
<!-- -->
|
||
|
|
</a>
|
||
|
|
<ul class="navList" title="Navigation">
|
||
|
|
<li><a href="../../../overview-summary.html">Overview</a></li>
|
||
|
|
<li><a href="package-summary.html">Package</a></li>
|
||
|
|
<li class="navBarCell1Rev">Class</li>
|
||
|
|
<li><a href="class-use/VertexCovers.html">Use</a></li>
|
||
|
|
<li><a href="package-tree.html">Tree</a></li>
|
||
|
|
<li><a href="../../../deprecated-list.html">Deprecated</a></li>
|
||
|
|
<li><a href="../../../index-all.html">Index</a></li>
|
||
|
|
<li><a href="../../../help-doc.html">Help</a></li>
|
||
|
|
</ul>
|
||
|
|
</div>
|
||
|
|
<div class="subNav">
|
||
|
|
<ul class="navList">
|
||
|
|
<li><a href="../../../org/jgrapht/alg/TransitiveReduction.html" title="class in org.jgrapht.alg"><span class="strong">Prev Class</span></a></li>
|
||
|
|
<li>Next Class</li>
|
||
|
|
</ul>
|
||
|
|
<ul class="navList">
|
||
|
|
<li><a href="../../../index.html?org/jgrapht/alg/VertexCovers.html" target="_top">Frames</a></li>
|
||
|
|
<li><a href="VertexCovers.html" target="_top">No Frames</a></li>
|
||
|
|
</ul>
|
||
|
|
<ul class="navList" id="allclasses_navbar_top">
|
||
|
|
<li><a href="../../../allclasses-noframe.html">All Classes</a></li>
|
||
|
|
</ul>
|
||
|
|
<div>
|
||
|
|
<script type="text/javascript"><!--
|
||
|
|
allClassesLink = document.getElementById("allclasses_navbar_top");
|
||
|
|
if(window==top) {
|
||
|
|
allClassesLink.style.display = "block";
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
allClassesLink.style.display = "none";
|
||
|
|
}
|
||
|
|
//-->
|
||
|
|
</script>
|
||
|
|
</div>
|
||
|
|
<div>
|
||
|
|
<ul class="subNavList">
|
||
|
|
<li>Summary: </li>
|
||
|
|
<li>Nested | </li>
|
||
|
|
<li>Field | </li>
|
||
|
|
<li><a href="#constructor_summary">Constr</a> | </li>
|
||
|
|
<li><a href="#method_summary">Method</a></li>
|
||
|
|
</ul>
|
||
|
|
<ul class="subNavList">
|
||
|
|
<li>Detail: </li>
|
||
|
|
<li>Field | </li>
|
||
|
|
<li><a href="#constructor_detail">Constr</a> | </li>
|
||
|
|
<li><a href="#method_detail">Method</a></li>
|
||
|
|
</ul>
|
||
|
|
</div>
|
||
|
|
<a name="skip-navbar_top">
|
||
|
|
<!-- -->
|
||
|
|
</a></div>
|
||
|
|
<!-- ========= END OF TOP NAVBAR ========= -->
|
||
|
|
<!-- ======== START OF CLASS DATA ======== -->
|
||
|
|
<div class="header">
|
||
|
|
<div class="subTitle">org.jgrapht.alg</div>
|
||
|
|
<h2 title="Class VertexCovers" class="title">Class VertexCovers</h2>
|
||
|
|
</div>
|
||
|
|
<div class="contentContainer">
|
||
|
|
<ul class="inheritance">
|
||
|
|
<li><a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">java.lang.Object</a></li>
|
||
|
|
<li>
|
||
|
|
<ul class="inheritance">
|
||
|
|
<li>org.jgrapht.alg.VertexCovers</li>
|
||
|
|
</ul>
|
||
|
|
</li>
|
||
|
|
</ul>
|
||
|
|
<div class="description">
|
||
|
|
<ul class="blockList">
|
||
|
|
<li class="blockList">
|
||
|
|
<hr>
|
||
|
|
<br>
|
||
|
|
<pre>public abstract class <span class="strong">VertexCovers</span>
|
||
|
|
extends <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</a></pre>
|
||
|
|
<div class="block">Algorithms to find a vertex cover for a graph. A vertex cover is a set of
|
||
|
|
vertices that touches all the edges in the graph. The graph's vertex set is a
|
||
|
|
trivial cover. However, a <i>minimal</i> vertex set (or at least an
|
||
|
|
approximation for it) is usually desired. Finding a true minimal vertex cover
|
||
|
|
is an NP-Complete problem. For more on the vertex cover problem, see <a
|
||
|
|
href="http://mathworld.wolfram.com/VertexCover.html">
|
||
|
|
http://mathworld.wolfram.com/VertexCover.html</a></div>
|
||
|
|
<dl><dt><span class="strong">Since:</span></dt>
|
||
|
|
<dd>Nov 6, 2003</dd>
|
||
|
|
<dt><span class="strong">Author:</span></dt>
|
||
|
|
<dd>Linda Buisman</dd></dl>
|
||
|
|
</li>
|
||
|
|
</ul>
|
||
|
|
</div>
|
||
|
|
<div class="summary">
|
||
|
|
<ul class="blockList">
|
||
|
|
<li class="blockList">
|
||
|
|
<!-- ======== CONSTRUCTOR SUMMARY ======== -->
|
||
|
|
<ul class="blockList">
|
||
|
|
<li class="blockList"><a name="constructor_summary">
|
||
|
|
<!-- -->
|
||
|
|
</a>
|
||
|
|
<h3>Constructor Summary</h3>
|
||
|
|
<table class="overviewSummary" border="0" cellpadding="3" cellspacing="0" summary="Constructor Summary table, listing constructors, and an explanation">
|
||
|
|
<caption><span>Constructors</span><span class="tabEnd"> </span></caption>
|
||
|
|
<tr>
|
||
|
|
<th class="colOne" scope="col">Constructor and Description</th>
|
||
|
|
</tr>
|
||
|
|
<tr class="altColor">
|
||
|
|
<td class="colOne"><code><strong><a href="../../../org/jgrapht/alg/VertexCovers.html#VertexCovers()">VertexCovers</a></strong>()</code> </td>
|
||
|
|
</tr>
|
||
|
|
</table>
|
||
|
|
</li>
|
||
|
|
</ul>
|
||
|
|
<!-- ========== METHOD SUMMARY =========== -->
|
||
|
|
<ul class="blockList">
|
||
|
|
<li class="blockList"><a name="method_summary">
|
||
|
|
<!-- -->
|
||
|
|
</a>
|
||
|
|
<h3>Method Summary</h3>
|
||
|
|
<table class="overviewSummary" border="0" cellpadding="3" cellspacing="0" summary="Method Summary table, listing methods, and an explanation">
|
||
|
|
<caption><span>Methods</span><span class="tabEnd"> </span></caption>
|
||
|
|
<tr>
|
||
|
|
<th class="colFirst" scope="col">Modifier and Type</th>
|
||
|
|
<th class="colLast" scope="col">Method and Description</th>
|
||
|
|
</tr>
|
||
|
|
<tr class="altColor">
|
||
|
|
<td class="colFirst"><code>static <V,E> <a href="http://docs.oracle.com/javase/7/docs/api/java/util/Set.html?is-external=true" title="class or interface in java.util">Set</a><V></code></td>
|
||
|
|
<td class="colLast"><code><strong><a href="../../../org/jgrapht/alg/VertexCovers.html#find2ApproximationCover(org.jgrapht.Graph)">find2ApproximationCover</a></strong>(<a href="../../../org/jgrapht/Graph.html" title="interface in org.jgrapht">Graph</a><V,E> g)</code>
|
||
|
|
<div class="block">Finds a 2-approximation for a minimal vertex cover of the specified
|
||
|
|
graph.</div>
|
||
|
|
</td>
|
||
|
|
</tr>
|
||
|
|
<tr class="rowColor">
|
||
|
|
<td class="colFirst"><code>static <V,E> <a href="http://docs.oracle.com/javase/7/docs/api/java/util/Set.html?is-external=true" title="class or interface in java.util">Set</a><V></code></td>
|
||
|
|
<td class="colLast"><code><strong><a href="../../../org/jgrapht/alg/VertexCovers.html#findGreedyCover(org.jgrapht.UndirectedGraph)">findGreedyCover</a></strong>(<a href="../../../org/jgrapht/UndirectedGraph.html" title="interface in org.jgrapht">UndirectedGraph</a><V,E> g)</code>
|
||
|
|
<div class="block">Finds a greedy approximation for a minimal vertex cover of a specified
|
||
|
|
graph.</div>
|
||
|
|
</td>
|
||
|
|
</tr>
|
||
|
|
</table>
|
||
|
|
<ul class="blockList">
|
||
|
|
<li class="blockList"><a name="methods_inherited_from_class_java.lang.Object">
|
||
|
|
<!-- -->
|
||
|
|
</a>
|
||
|
|
<h3>Methods inherited from class java.lang.<a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</a></h3>
|
||
|
|
<code><a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#clone()" title="class or interface in java.lang">clone</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#equals(java.lang.Object)" title="class or interface in java.lang">equals</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#finalize()" title="class or interface in java.lang">finalize</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#getClass()" title="class or interface in java.lang">getClass</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#hashCode()" title="class or interface in java.lang">hashCode</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#notify()" title="class or interface in java.lang">notify</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#notifyAll()" title="class or interface in java.lang">notifyAll</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#toString()" title="class or interface in java.lang">toString</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#wait()" title="class or interface in java.lang">wait</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#wait(long)" title="class or interface in java.lang">wait</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#wait(long,%20int)" title="class or interface in java.lang">wait</a></code></li>
|
||
|
|
</ul>
|
||
|
|
</li>
|
||
|
|
</ul>
|
||
|
|
</li>
|
||
|
|
</ul>
|
||
|
|
</div>
|
||
|
|
<div class="details">
|
||
|
|
<ul class="blockList">
|
||
|
|
<li class="blockList">
|
||
|
|
<!-- ========= CONSTRUCTOR DETAIL ======== -->
|
||
|
|
<ul class="blockList">
|
||
|
|
<li class="blockList"><a name="constructor_detail">
|
||
|
|
<!-- -->
|
||
|
|
</a>
|
||
|
|
<h3>Constructor Detail</h3>
|
||
|
|
<a name="VertexCovers()">
|
||
|
|
<!-- -->
|
||
|
|
</a>
|
||
|
|
<ul class="blockListLast">
|
||
|
|
<li class="blockList">
|
||
|
|
<h4>VertexCovers</h4>
|
||
|
|
<pre>public VertexCovers()</pre>
|
||
|
|
</li>
|
||
|
|
</ul>
|
||
|
|
</li>
|
||
|
|
</ul>
|
||
|
|
<!-- ============ METHOD DETAIL ========== -->
|
||
|
|
<ul class="blockList">
|
||
|
|
<li class="blockList"><a name="method_detail">
|
||
|
|
<!-- -->
|
||
|
|
</a>
|
||
|
|
<h3>Method Detail</h3>
|
||
|
|
<a name="find2ApproximationCover(org.jgrapht.Graph)">
|
||
|
|
<!-- -->
|
||
|
|
</a>
|
||
|
|
<ul class="blockList">
|
||
|
|
<li class="blockList">
|
||
|
|
<h4>find2ApproximationCover</h4>
|
||
|
|
<pre>public static <V,E> <a href="http://docs.oracle.com/javase/7/docs/api/java/util/Set.html?is-external=true" title="class or interface in java.util">Set</a><V> find2ApproximationCover(<a href="../../../org/jgrapht/Graph.html" title="interface in org.jgrapht">Graph</a><V,E> g)</pre>
|
||
|
|
<div class="block">Finds a 2-approximation for a minimal vertex cover of the specified
|
||
|
|
graph. The algorithm promises a cover that is at most double the size of
|
||
|
|
a minimal cover. The algorithm takes O(|E|) time.
|
||
|
|
|
||
|
|
<p>For more details see Jenny Walter, CMPU-240: Lecture notes for
|
||
|
|
Language Theory and Computation, Fall 2002, Vassar College, <a
|
||
|
|
href="http://www.cs.vassar.edu/~walter/cs241index/lectures/PDF/approx.pdf">
|
||
|
|
http://www.cs.vassar.edu/~walter/cs241index/lectures/PDF/approx.pdf</a>.
|
||
|
|
</p></div>
|
||
|
|
<dl><dt><span class="strong">Parameters:</span></dt><dd><code>g</code> - the graph for which vertex cover approximation is to be found.</dd>
|
||
|
|
<dt><span class="strong">Returns:</span></dt><dd>a set of vertices which is a vertex cover for the specified
|
||
|
|
graph.</dd></dl>
|
||
|
|
</li>
|
||
|
|
</ul>
|
||
|
|
<a name="findGreedyCover(org.jgrapht.UndirectedGraph)">
|
||
|
|
<!-- -->
|
||
|
|
</a>
|
||
|
|
<ul class="blockListLast">
|
||
|
|
<li class="blockList">
|
||
|
|
<h4>findGreedyCover</h4>
|
||
|
|
<pre>public static <V,E> <a href="http://docs.oracle.com/javase/7/docs/api/java/util/Set.html?is-external=true" title="class or interface in java.util">Set</a><V> findGreedyCover(<a href="../../../org/jgrapht/UndirectedGraph.html" title="interface in org.jgrapht">UndirectedGraph</a><V,E> g)</pre>
|
||
|
|
<div class="block">Finds a greedy approximation for a minimal vertex cover of a specified
|
||
|
|
graph. At each iteration, the algorithm picks the vertex with the highest
|
||
|
|
degree and adds it to the cover, until all edges are covered.
|
||
|
|
|
||
|
|
<p>The algorithm works on undirected graphs, but can also work on
|
||
|
|
directed graphs when their edge-directions are ignored. To ignore edge
|
||
|
|
directions you can use <a href="../../../org/jgrapht/Graphs.html#undirectedGraph(org.jgrapht.Graph)"><code>Graphs.undirectedGraph(Graph)</code></a>
|
||
|
|
or <a href="../../../org/jgrapht/graph/AsUndirectedGraph.html" title="class in org.jgrapht.graph"><code>AsUndirectedGraph</code></a>.</p></div>
|
||
|
|
<dl><dt><span class="strong">Parameters:</span></dt><dd><code>g</code> - the graph for which vertex cover approximation is to be found.</dd>
|
||
|
|
<dt><span class="strong">Returns:</span></dt><dd>a set of vertices which is a vertex cover for the specified
|
||
|
|
graph.</dd></dl>
|
||
|
|
</li>
|
||
|
|
</ul>
|
||
|
|
</li>
|
||
|
|
</ul>
|
||
|
|
</li>
|
||
|
|
</ul>
|
||
|
|
</div>
|
||
|
|
</div>
|
||
|
|
<!-- ========= END OF CLASS DATA ========= -->
|
||
|
|
<!-- ======= START OF BOTTOM NAVBAR ====== -->
|
||
|
|
<div class="bottomNav"><a name="navbar_bottom">
|
||
|
|
<!-- -->
|
||
|
|
</a><a href="#skip-navbar_bottom" title="Skip navigation links"></a><a name="navbar_bottom_firstrow">
|
||
|
|
<!-- -->
|
||
|
|
</a>
|
||
|
|
<ul class="navList" title="Navigation">
|
||
|
|
<li><a href="../../../overview-summary.html">Overview</a></li>
|
||
|
|
<li><a href="package-summary.html">Package</a></li>
|
||
|
|
<li class="navBarCell1Rev">Class</li>
|
||
|
|
<li><a href="class-use/VertexCovers.html">Use</a></li>
|
||
|
|
<li><a href="package-tree.html">Tree</a></li>
|
||
|
|
<li><a href="../../../deprecated-list.html">Deprecated</a></li>
|
||
|
|
<li><a href="../../../index-all.html">Index</a></li>
|
||
|
|
<li><a href="../../../help-doc.html">Help</a></li>
|
||
|
|
</ul>
|
||
|
|
</div>
|
||
|
|
<div class="subNav">
|
||
|
|
<ul class="navList">
|
||
|
|
<li><a href="../../../org/jgrapht/alg/TransitiveReduction.html" title="class in org.jgrapht.alg"><span class="strong">Prev Class</span></a></li>
|
||
|
|
<li>Next Class</li>
|
||
|
|
</ul>
|
||
|
|
<ul class="navList">
|
||
|
|
<li><a href="../../../index.html?org/jgrapht/alg/VertexCovers.html" target="_top">Frames</a></li>
|
||
|
|
<li><a href="VertexCovers.html" target="_top">No Frames</a></li>
|
||
|
|
</ul>
|
||
|
|
<ul class="navList" id="allclasses_navbar_bottom">
|
||
|
|
<li><a href="../../../allclasses-noframe.html">All Classes</a></li>
|
||
|
|
</ul>
|
||
|
|
<div>
|
||
|
|
<script type="text/javascript"><!--
|
||
|
|
allClassesLink = document.getElementById("allclasses_navbar_bottom");
|
||
|
|
if(window==top) {
|
||
|
|
allClassesLink.style.display = "block";
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
allClassesLink.style.display = "none";
|
||
|
|
}
|
||
|
|
//-->
|
||
|
|
</script>
|
||
|
|
</div>
|
||
|
|
<div>
|
||
|
|
<ul class="subNavList">
|
||
|
|
<li>Summary: </li>
|
||
|
|
<li>Nested | </li>
|
||
|
|
<li>Field | </li>
|
||
|
|
<li><a href="#constructor_summary">Constr</a> | </li>
|
||
|
|
<li><a href="#method_summary">Method</a></li>
|
||
|
|
</ul>
|
||
|
|
<ul class="subNavList">
|
||
|
|
<li>Detail: </li>
|
||
|
|
<li>Field | </li>
|
||
|
|
<li><a href="#constructor_detail">Constr</a> | </li>
|
||
|
|
<li><a href="#method_detail">Method</a></li>
|
||
|
|
</ul>
|
||
|
|
</div>
|
||
|
|
<a name="skip-navbar_bottom">
|
||
|
|
<!-- -->
|
||
|
|
</a></div>
|
||
|
|
<!-- ======== END OF BOTTOM NAVBAR ======= -->
|
||
|
|
<p class="legalCopy"><small>Copyright © 2016. All rights reserved.</small></p>
|
||
|
|
</body>
|
||
|
|
</html>
|