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<h2>geom.c, geom2.c -- geometric and floating point routines</h2>
<blockquote>
<p>Geometrically, a vertex is a point with <em>d</em> coordinates
and a facet is a halfspace. A <em>halfspace</em> is defined by an
oriented hyperplane through the facet's vertices. A <em>hyperplane</em>
is defined by <em>d</em> normalized coefficients and an offset. A
point is <em>above</em> a facet if its distance to the facet is
positive.</p>
<p>Qhull uses floating point coordinates for input points,
vertices, halfspace equations, centrums, and an interior point.</p>
<p>Qhull may be configured for single precision or double
precision floating point arithmetic (see <a href="user.h#realT">realT</a>
). </p>
<p>Each floating point operation may incur round-off error (see
<a href="qh-merge.htm#TOC">Merge</a>). The maximum error for distance
computations is determined at initialization. The roundoff error
in halfspace computation is accounted for by computing the
distance from vertices to the halfspace. </p>
</blockquote>
<p><b>Copyright © 1995-2003 The Geometry Center, Minneapolis MN</b></p>
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