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<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Hi Lavanya,<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>You could consider using pgRouting (http://www.postlbs.org/) .<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>This extension to Postgres/PostGIS needs some topology and topology
support for PostGIS is still in its infancy and barely documented… </span><span
lang=EN-US style='font-size:11.0pt;font-family:Wingdings;color:#1F497D'>L</span><span
lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Now to implement ‘topology’ the *<b>easy</b>* way…
;-)<o:p></o:p></span></p>
<p class=MsoNormal><b><span lang=EN-US style='font-size:11.0pt;font-family:
"Calibri","sans-serif";color:#1F497D'>Use OpenJump!</span></b><span lang=EN-US
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> (<a
href="http://openjump.org">http://openjump.org</a>)<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>There’s a tool there called ‘Planar Graph’…<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>You can use it to get every line segment documented (start and
end nodes for each line).<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Add a ‘length’ field to your dataset.<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>OpenJump also has a tool to calculate areas and lengths…
;-)<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Save your dataset from OpenJump into PostGIS.<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>The ‘length’ field acts as an initial cost for
turning….<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Then use the shortest_path() function from pgRouting and you’re
on your way!<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Also heard from the developers of pgRouting that support for
turn restrictions is somewhere in the near future… ;-)<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>(OJ People</span><span lang=EN-US style='font-size:11.0pt;
font-family:Wingdings;color:#1F497D'>à</span><span lang=EN-US
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> I’m
posting this to the list as I think it’s useful ;-) )<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>HTH,<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Pedro Doria Meunier<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'>
<p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:
"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;
font-family:"Tahoma","sans-serif"'>
postgis-users-bounces@postgis.refractions.net
[mailto:postgis-users-bounces@postgis.refractions.net] <b>On Behalf Of </b>Lavanya
A<br>
<b>Sent:</b> segunda-feira, 19 de Fevereiro de 2007 13:42<br>
<b>To:</b> postgis-users@postgis.refractions.net<br>
<b>Subject:</b> [postgis-users] help plz<o:p></o:p></span></p>
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<p class=MsoNormal><o:p> </o:p></p>
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<p class=MsoNormal>Hi,<o:p></o:p></p>
</div>
<div>
<p class=MsoNormal> <o:p></o:p></p>
</div>
<div>
<p class=MsoNormal>Jus need few help from u...im currently using postgres 8.2
and PostGIS 1.2.1..<o:p></o:p></p>
</div>
<div>
<p class=MsoNormal> <o:p></o:p></p>
</div>
<div>
<p class=MsoNormal>I have few shapefile, especially roads..which im working on
it..<o:p></o:p></p>
</div>
<div>
<p class=MsoNormal> <o:p></o:p></p>
</div>
<div>
<p class=MsoNormal>I need to find the route between two points, namely a <em>latitude
and longitude</em> to a <em>place of interest</em>. I thought i should network
analysis. But not sure of what to use and how to achieve my goal.<o:p></o:p></p>
</div>
<div>
<p class=MsoNormal> <o:p></o:p></p>
</div>
<div>
<p class=MsoNormal>Can u suggest me wat tool should i use and any special query
will do using postgres? Please i seek ur suggestion<o:p></o:p></p>
</div>
<div>
<p class=MsoNormal> <o:p></o:p></p>
</div>
<div>
<p class=MsoNormal>Regards<o:p></o:p></p>
</div>
<div>
<p class=MsoNormal>Lavanya A<o:p></o:p></p>
</div>
<div>
<p class=MsoNormal> <o:p></o:p></p>
</div>
<div>
<p class=MsoNormal> <o:p></o:p></p>
</div>
<div>
<p class=MsoNormal> <o:p></o:p></p>
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<p class=MsoNormal> <o:p></o:p></p>
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<p> <o:p></o:p></p>
<div class=MsoNormal align=center style='text-align:center'>
<hr size=1 width="100%" align=center>
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<p class=MsoNormal>Here’s a new way to find what you're looking for - <a
href="http://us.rd.yahoo.com/mail/in/yanswers/*http:/in.answers.yahoo.com/">Yahoo!
Answers</a> <o:p></o:p></p>
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