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<div class=Section1>
<p class=MsoNormal><font size=2 face=Arial><span lang=ET style='font-size:10.0pt;
font-family:Arial'>The pgDijkstra algorithm assigns to each RoadSegment a
unique EdgeID in graph. While assigning EdgeID, it expects that road segment
start and end point to be unique. This worked fine for our sample data (a
small area of Basingstoke) but in London some road segments have the same start
and end point (with a number of additional points in the middle which are
different).<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=ET style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=ET style='font-size:10.0pt;
font-family:Arial'>For example two distinct road segments: <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=ET style='font-size:10.0pt;
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185330.493</span></b>,524106.899 185325.348,524112.444 185319.119,<b><span
style='font-weight:bold'>524118 185318</span></b>)<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=ET style='font-size:10.0pt;
font-family:Arial'>LINESTRING(<b><span style='font-weight:bold'>524107.31
185330.493</span></b>,524111.088 185329.479,524111.761 185329.298,524117.382
185322.233,<b><span style='font-weight:bold'>524118 185318</span></b>)<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'>What can we do to overcome this problem?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 color=teal face=Arial><span lang=FR
style='font-size:9.0pt;font-family:Arial;color:teal'>--------------------------<br>
Graham McConney</span></font><font size=2 face=Arial><span lang=EN-US
style='font-size:10.0pt;font-family:Arial'><br>
---<br>
</span></font><font size=1 face=Arial><span lang=EN-US style='font-size:7.5pt;
font-family:Arial'>Email scanned for viruses</span></font><span lang=EN-US><o:p></o:p></span></p>
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style='font-size:12.0pt'><o:p> </o:p></span></font></p>
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