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<p class="MsoNormal">Greetings,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I have some questions on ST_Snap on linestrings:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The other day Martin Davis commented on the GEOS list:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-left:36.0pt">The ultimate solution is perform snap-rounding over the entire input set. I don't think ST_Snap is doing this - AFAIK it's doing some heuristic-based snapping only.<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:36.0pt"><o:p> </o:p></p>
<p class="MsoNormal">I was under the impression that ST_Snap(a, b, x) snapped geom a to geom b within precision x. My understanding was that in practice this means that all lines in geom a are snapped to geom b if they are within x.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Am I misunderstanding how this works, or am I misunderstanding snap-rounding? Comments?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-bottom:12.0pt"><span style="font-size:9.0pt;font-family:"Verdana","sans-serif"">Cheers,<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-bottom:12.0pt"><span style="font-size:9.0pt;font-family:"Verdana","sans-serif";color:#999999">James Sewell </span><span style="font-size:9.0pt;font-family:"Verdana","sans-serif";color:#999999"><br>
</span><span style="font-size:9.0pt;font-family:"Verdana","sans-serif";color:#999999">Solutions Architect </span><span style="font-size:9.0pt;font-family:"Verdana","sans-serif";color:#999999"><br>
</span><span style="font-size:9.0pt;font-family:"Verdana","sans-serif";color:#999999">LISAsoft </span><span style="font-size:9.0pt;font-family:"Verdana","sans-serif";color:#999999"><o:p></o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:9.0pt;font-family:"Verdana","sans-serif";color:#999999">Ph: </span></b><span style="font-size:9.0pt;font-family:"Verdana","sans-serif";color:#999999">+61 3 8680 3250 <b>Fax: </b>+61 3 8680 3299 </span><span style="font-size:9.0pt;font-family:"Verdana","sans-serif";color:#999999"><br>
</span><span style="font-size:9.0pt;font-family:"Verdana","sans-serif";color:#999999">Level 9, 601 Bourke St, Melbourne Vic 3000<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Verdana","sans-serif";color:#999999"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Verdana","sans-serif";color:#4F81BD"><a href="http://www.lisasoft.com/"><span style="color:#4F81BD;text-decoration:none">http://www.lisasoft.com</span></a></span><span style="font-size:9.0pt;font-family:"Verdana","sans-serif";color:#999999"><br>
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