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    GEOS uses the same algorithm for the binary predicates as JTS.<br>
    <br>
    Unfortunately, recently a GEOS ticket was filed that revealed a
    small robustness problem with the predicates in certain Line/Line
    situations.  (<a class="moz-txt-link-freetext" href="http://trac.osgeo.org/geos/ticket/572">http://trac.osgeo.org/geos/ticket/572</a>).  Currently
    there's no resolution for this problem, but it's being actively
    researched.<br>
    <br>
    <div class="moz-cite-prefix">On 8/27/2012 3:38 AM, Jasmin FORMONT
      wrote:<br>
    </div>
    <blockquote
cite="mid:4DDD462E988B52488DA728A04EF7C5745EB2A03FE1@Eucles.Siradel.local"
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        <p class="MsoNormal">Hi everyone,<o:p></o:p></p>
        <p class="MsoNormal"><o:p> </o:p></p>
        <p class="MsoNormal"><span lang="EN-US">I have a question
            concerning the precision of predicates, and mainly touches.
            On the JTS website, I read “</span><span
style="font-size:10.0pt;font-family:"Verdana","sans-serif";color:black;background:white"
            lang="EN-US">The algorithms used to implement the SFS
            predicates and functions have been developed to eliminate or
            minimize robustness problems. The binary predicate algorithm
            is completely robust.”<o:p></o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:10.0pt;font-family:"Verdana","sans-serif";color:black;background:white"
            lang="EN-US"><o:p> </o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:10.0pt;font-family:"Verdana","sans-serif";color:black;background:white"
            lang="EN-US">In GEOS, is combinatorial also used for the
            binary predicates, and are they totally robust ?<o:p></o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:10.0pt;font-family:"Verdana","sans-serif";color:black;background:white"
            lang="EN-US"><o:p> </o:p></span></p>
        <br>
      </div>
    </blockquote>
    <br>
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