iginal extreme points. With
imprecise halfspaces and exact arithmetic, nearly incident points
may be returned for an original extreme point. By handling
roundoff error, Qhull returns one intersection point for each of
the original extreme points. Qhull may split or merge an extreme
point, but this appears to be unlikely.</p>

<p>The following pipe implements the identity function for
extreme points (with roundoff):
<blockquote>
    qconvex <a href="qh-optf.htm#FV">FV</a> <a
    href="qh-opto.htm#n">n</a> | 