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<div>It would be easier to create new points rather than modifying the returned route?</div>
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<div>I'll take a look at the repo link.</div>
<div>Thanks!</div>
<div>Best,<br>
Steve</div>
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<span style="font-size:14.0pt; font-family:"Arial","sans-serif"; color:#006C56">Stephen V. Mather<br>
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<div id="divRpF667533" style="direction: ltr;"><font face="Tahoma" size="2" color="#000000"><b>From:</b> pgrouting-users-bounces@lists.osgeo.org [pgrouting-users-bounces@lists.osgeo.org] on behalf of Daniel Kastl [daniel@georepublic.de]<br>
<b>Sent:</b> Friday, April 12, 2013 11:16 PM<br>
<b>To:</b> pgRouting users mailing list<br>
<b>Subject:</b> Re: [pgrouting-users] A* vs. Dijkstra and the nature of the A* implementation<br>
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For datasets as large as the one we are working with, this seems to<br>
result in a pretty high random IO tax. I wondered if anyone has some<br>
boilerplate modifying the returned route, slicing the nearest ways to<br>
the beginning and end points with ST_ClosestPoint or similar?<br>
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I have done this, it is not that hard.<br>
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<div style="">As Steve said, this is not so hard. You can select the closest point on the nearest road segment and PostGIS has all the function to gibe you a substring from that point.</div>
<div style="">There is an example how to do this with Shooting Star, which has some problems at the moment, but just to get an idea: <a href="https://github.com/pgRouting/pgrouting/blob/sew-devel-2_0/src/common/sql/pgrouting_network_check.sql" target="_blank">https://github.com/pgRouting/pgrouting/blob/sew-devel-2_0/src/common/sql/pgrouting_network_check.sql</a></div>
<div style="">Shooting Star routes from road segment to road segment, so the logic is slightly different. For other algorithms such as TRSP you probably need to create a temporary node.</div>
<div style="">So in short, I wouldn't modify the returned route but start from new points.</div>
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<div style="">Daniel </div>
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-- <br>
<span style="font-family:arial,sans-serif; font-size:13px; border-collapse:collapse">Georepublic UG & Georepublic Japan<br>
eMail: <a href="mailto:daniel.kastl@georepublic.de" style="color:rgb(66,99,171)" target="_blank">daniel.kastl@georepublic.de</a><br>
Web: <a href="http://georepublic.de/" style="color:rgb(66,99,171)" target="_blank">http://georepublic.de</a></span>
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