1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>discrete_frechet_distance</title> 5<link rel="stylesheet" href="../../../../../../../../doc/src/boostbook.css" type="text/css"> 6<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 7<link rel="home" href="../../../../index.html" title="Chapter 1. Geometry"> 8<link rel="up" href="../discrete_frechet_distance.html" title="discrete_frechet_distance"> 9<link rel="prev" href="discrete_frechet_distance_3_with_strategy.html" title="discrete_frechet_distance (with strategy)"> 10<link rel="next" href="../discrete_hausdorff_distance.html" title="discrete_hausdorff_distance"> 11</head> 12<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 13<table cellpadding="2" width="100%"><tr> 14<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../../../../boost.png"></td> 15<td align="center"><a href="../../../../../../../../index.html">Home</a></td> 16<td align="center"><a href="../../../../../../../../libs/libraries.htm">Libraries</a></td> 17<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> 18<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> 19<td align="center"><a href="../../../../../../../../more/index.htm">More</a></td> 20</tr></table> 21<hr> 22<div class="spirit-nav"> 23<a accesskey="p" href="discrete_frechet_distance_3_with_strategy.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../discrete_frechet_distance.html"><img src="../../../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../../index.html"><img src="../../../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="../discrete_hausdorff_distance.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> 24</div> 25<div class="section"> 26<div class="titlepage"><div><div><h5 class="title"> 27<a name="geometry.reference.algorithms.discrete_frechet_distance.discrete_frechet_distance_2"></a><a class="link" href="discrete_frechet_distance_2.html" title="discrete_frechet_distance">discrete_frechet_distance</a> 28</h5></div></div></div> 29<p> 30 <a class="indexterm" name="idm45635700919424"></a> 31Calculate discrete Frechet distance between two geometries (currently 32 work for LineString-LineString). 33 </p> 34<h6> 35<a name="geometry.reference.algorithms.discrete_frechet_distance.discrete_frechet_distance_2.h0"></a> 36 <span class="phrase"><a name="geometry.reference.algorithms.discrete_frechet_distance.discrete_frechet_distance_2.synopsis"></a></span><a class="link" href="discrete_frechet_distance_2.html#geometry.reference.algorithms.discrete_frechet_distance.discrete_frechet_distance_2.synopsis">Synopsis</a> 37 </h6> 38<p> 39</p> 40<pre class="programlisting"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Geometry1</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Geometry2</span><span class="special">></span> 41<span class="identifier">distance_result</span><span class="special"><</span> <span class="keyword">typename</span> <span class="identifier">point_type</span><span class="special"><</span><span class="identifier">Geometry1</span><span class="special">>::</span><span class="identifier">type</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">point_type</span><span class="special"><</span><span class="identifier">Geometry2</span><span class="special">>::</span><span class="identifier">type</span> <span class="special">>::</span><span class="identifier">type</span> <span class="identifier">discrete_frechet_distance</span><span class="special">(</span><span class="identifier">Geometry1</span> <span class="keyword">const</span> <span class="special">&</span> <span class="identifier">geometry1</span><span class="special">,</span> <span class="identifier">Geometry2</span> <span class="keyword">const</span> <span class="special">&</span> <span class="identifier">geometry2</span><span class="special">)</span></pre> 42<p> 43 </p> 44<h6> 45<a name="geometry.reference.algorithms.discrete_frechet_distance.discrete_frechet_distance_2.h1"></a> 46 <span class="phrase"><a name="geometry.reference.algorithms.discrete_frechet_distance.discrete_frechet_distance_2.parameters"></a></span><a class="link" href="discrete_frechet_distance_2.html#geometry.reference.algorithms.discrete_frechet_distance.discrete_frechet_distance_2.parameters">Parameters</a> 47 </h6> 48<div class="informaltable"><table class="table"> 49<colgroup> 50<col> 51<col> 52<col> 53<col> 54</colgroup> 55<thead><tr> 56<th> 57 <p> 58 Type 59 </p> 60 </th> 61<th> 62 <p> 63 Concept 64 </p> 65 </th> 66<th> 67 <p> 68 Name 69 </p> 70 </th> 71<th> 72 <p> 73 Description 74 </p> 75 </th> 76</tr></thead> 77<tbody> 78<tr> 79<td> 80 <p> 81 Geometry1 const & 82 </p> 83 </td> 84<td> 85 <p> 86 Any type fulfilling a Geometry Concept 87 </p> 88 </td> 89<td> 90 <p> 91 geometry1 92 </p> 93 </td> 94<td> 95 <p> 96 Input geometry 97 </p> 98 </td> 99</tr> 100<tr> 101<td> 102 <p> 103 Geometry2 const & 104 </p> 105 </td> 106<td> 107 <p> 108 Any type fulfilling a Geometry Concept 109 </p> 110 </td> 111<td> 112 <p> 113 geometry2 114 </p> 115 </td> 116<td> 117 <p> 118 Input geometry 119 </p> 120 </td> 121</tr> 122</tbody> 123</table></div> 124<h6> 125<a name="geometry.reference.algorithms.discrete_frechet_distance.discrete_frechet_distance_2.h2"></a> 126 <span class="phrase"><a name="geometry.reference.algorithms.discrete_frechet_distance.discrete_frechet_distance_2.header"></a></span><a class="link" href="discrete_frechet_distance_2.html#geometry.reference.algorithms.discrete_frechet_distance.discrete_frechet_distance_2.header">Header</a> 127 </h6> 128<p> 129 Either 130 </p> 131<p> 132 <code class="computeroutput"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">geometry</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span></code> 133 </p> 134<p> 135 Or 136 </p> 137<p> 138 <code class="computeroutput"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">geometry</span><span class="special">/</span><span class="identifier">algorithms</span><span class="special">/</span><span class="identifier">discrete_frechet_distance</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span></code> 139 </p> 140<h6> 141<a name="geometry.reference.algorithms.discrete_frechet_distance.discrete_frechet_distance_2.h3"></a> 142 <span class="phrase"><a name="geometry.reference.algorithms.discrete_frechet_distance.discrete_frechet_distance_2.behavior"></a></span><a class="link" href="discrete_frechet_distance_2.html#geometry.reference.algorithms.discrete_frechet_distance.discrete_frechet_distance_2.behavior">Behavior</a> 143 </h6> 144<p> 145 The algorithm calculate discrete frechet distance between two geometries. 146 </p> 147<div class="note"><table border="0" summary="Note"> 148<tr> 149<td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../../../../../../../doc/src/images/note.png"></td> 150<th align="left">Note</th> 151</tr> 152<tr><td align="left" valign="top"><p> 153 The units of the distance depends on strategy. In order to change the 154 default behavior a user has to create a strategy and pass it explicitly 155 into the algorithm. 156 </p></td></tr> 157</table></div> 158<h6> 159<a name="geometry.reference.algorithms.discrete_frechet_distance.discrete_frechet_distance_2.h4"></a> 160 <span class="phrase"><a name="geometry.reference.algorithms.discrete_frechet_distance.discrete_frechet_distance_2.example"></a></span><a class="link" href="discrete_frechet_distance_2.html#geometry.reference.algorithms.discrete_frechet_distance.discrete_frechet_distance_2.example">Example</a> 161 </h6> 162<p> 163 Calculate Similarity between two geometries as the discrete frechet distance 164 between them. 165 </p> 166<p> 167</p> 168<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">iostream</span><span class="special">></span> 169 170<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">geometry</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> 171<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">geometry</span><span class="special">/</span><span class="identifier">geometries</span><span class="special">/</span><span class="identifier">point_xy</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> 172<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">geometry</span><span class="special">/</span><span class="identifier">geometries</span><span class="special">/</span><span class="identifier">linestring</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> 173 174<span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span> 175<span class="special">{</span> 176 <span class="keyword">typedef</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">geometry</span><span class="special">::</span><span class="identifier">model</span><span class="special">::</span><span class="identifier">d2</span><span class="special">::</span><span class="identifier">point_xy</span><span class="special"><</span><span class="keyword">double</span><span class="special">></span> <span class="identifier">point_type</span><span class="special">;</span> 177 <span class="keyword">typedef</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">geometry</span><span class="special">::</span><span class="identifier">model</span><span class="special">::</span><span class="identifier">linestring</span><span class="special"><</span><span class="identifier">point_type</span><span class="special">></span> <span class="identifier">linestring_type</span><span class="special">;</span> 178 179 <span class="identifier">linestring_type</span> <span class="identifier">ls1</span><span class="special">,</span> <span class="identifier">ls2</span><span class="special">;</span> 180 <span class="identifier">boost</span><span class="special">::</span><span class="identifier">geometry</span><span class="special">::</span><span class="identifier">read_wkt</span><span class="special">(</span><span class="string">"LINESTRING(0 0,1 1,1 2,2 1,2 2)"</span><span class="special">,</span> <span class="identifier">ls1</span><span class="special">);</span> 181 <span class="identifier">boost</span><span class="special">::</span><span class="identifier">geometry</span><span class="special">::</span><span class="identifier">read_wkt</span><span class="special">(</span><span class="string">"LINESTRING(1 0,0 1,1 1,2 1,3 1)"</span><span class="special">,</span> <span class="identifier">ls2</span><span class="special">);</span> 182 183 <span class="keyword">double</span> <span class="identifier">res</span> <span class="special">=</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">geometry</span><span class="special">::</span><span class="identifier">discrete_frechet_distance</span><span class="special">(</span><span class="identifier">ls1</span><span class="special">,</span> <span class="identifier">ls2</span><span class="special">);</span> 184 185 <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"Discrete Frechet Distance: "</span> <span class="special"><<</span> <span class="identifier">res</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> 186 187 <span class="keyword">return</span> <span class="number">0</span><span class="special">;</span> 188<span class="special">}</span> 189</pre> 190<p> 191 </p> 192<p> 193 Output: 194 </p> 195<pre class="programlisting">Discrete Frechet Distance: 1.41421 196</pre> 197</div> 198<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 199<td align="left"></td> 200<td align="right"><div class="copyright-footer">Copyright © 2009-2019 Barend Gehrels, Bruno Lalande, Mateusz Loskot, Adam 201 Wulkiewicz, Oracle and/or its affiliates<p> 202 Distributed under the Boost Software License, Version 1.0. (See accompanying 203 file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>) 204 </p> 205</div></td> 206</tr></table> 207<hr> 208<div class="spirit-nav"> 209<a accesskey="p" href="discrete_frechet_distance_3_with_strategy.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../discrete_frechet_distance.html"><img src="../../../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../../index.html"><img src="../../../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="../discrete_hausdorff_distance.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> 210</div> 211</body> 212</html> 213
