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<li><a class="el" href="classgeos_1_1algorithm_1_1RobustDeterminant.html">geos::algorithm::RobustDeterminant</a> </li>
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<h1>geos::algorithm::RobustDeterminant Class Reference</h1> </div>
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<!-- doxytag: class="geos::algorithm::RobustDeterminant" -->
<p>Implements an algorithm to compute the sign of a 2x2 determinant for double precision values robustly.
<a href="#_details">More...</a></p>
<p><code>#include <<a class="el" href="RobustDeterminant_8h_source.html">RobustDeterminant.h</a>></code></p>
<p><a href="classgeos_1_1algorithm_1_1RobustDeterminant-members.html">List of all members.</a></p>
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<tr><td colspan="2"><h2><a name="pub-static-methods"></a>
Static Public Member Functions</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">static int </td><td class="memItemRight" valign="bottom"><a class="el" href="classgeos_1_1algorithm_1_1RobustDeterminant.html#aa4281973e2c4ae3940eeb1ad3aaa0dd2">signOfDet2x2</a> (double x1, double y1, double x2, double y2)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Computes the sign of the determinant of the 2x2 matrix with the given entries, in a robust way. <a href="#aa4281973e2c4ae3940eeb1ad3aaa0dd2"></a><br/></td></tr>
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<hr/><a name="_details"></a><h2>Detailed Description</h2>
<p>Implements an algorithm to compute the sign of a 2x2 determinant for double precision values robustly. </p>
<p>It is a direct translation of code developed by Olivier Devillers.</p>
<p>The original code carries the following copyright notice:</p>
<pre></pre><pre> The original code carries the following copyright notice:
Author : Olivier Devillers
<a href="mailto:Olivier.Devillers@sophia.inria.fr">Olivier.Devillers@sophia.inria.fr</a>
<a href="http:/www.inria.fr:/prisme/personnel/devillers/anglais/determinant.html">http:/www.inria.fr:/prisme/personnel/devillers/anglais/determinant.html</a></pre><pre> Copyright (c) 1995 by INRIA Prisme Project
BP 93 06902 Sophia Antipolis Cedex, France.
All rights reserved</pre><pre> </pre> <hr/><h2>Member Function Documentation</h2>
<a class="anchor" id="aa4281973e2c4ae3940eeb1ad3aaa0dd2"></a><!-- doxytag: member="geos::algorithm::RobustDeterminant::signOfDet2x2" ref="aa4281973e2c4ae3940eeb1ad3aaa0dd2" args="(double x1, double y1, double x2, double y2)" -->
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<td class="memname">static int geos::algorithm::RobustDeterminant::signOfDet2x2 </td>
<td>(</td>
<td class="paramtype">double </td>
<td class="paramname"> <em>x1</em>, </td>
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<td class="paramkey"></td>
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<td class="paramtype">double </td>
<td class="paramname"> <em>y1</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">double </td>
<td class="paramname"> <em>x2</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">double </td>
<td class="paramname"> <em>y2</em></td><td> </td>
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<td></td>
<td>)</td>
<td></td><td></td><td><code> [static]</code></td>
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<p>Computes the sign of the determinant of the 2x2 matrix with the given entries, in a robust way. </p>
<dl class="return"><dt><b>Returns:</b></dt><dd>-1 if the determinant is negative, </dd>
<dd>
1 if the determinant is positive, </dd>
<dd>
0 if the determinant is 0. </dd></dl>
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<hr/>The documentation for this class was generated from the following file:<ul>
<li><a class="el" href="RobustDeterminant_8h_source.html">RobustDeterminant.h</a></li>
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