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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hi everyone:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><span style='mso-spacerun:yes'> </span>I am trying to use <span
class=SpellE>pgDijkstra</span> in my project. <span class=SpellE><span
class=GramE>pgDijkstra</span></span> calls boost library which provides
single-source shortest function. My network is a street network. The graph is directed.
My typical scenario is, there is one client calls dispatch center and there are
many cars (for example, 100 cars) are available all over the network. I want to
find the closet car and dispatch it to the client. It is a single-destination
problem. Does anyone know if there is an existing single-destination program
exists available for my project? <span class=GramE>Or the explanation of the single-destination
algorithm?</span><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><span style='mso-spacerun:yes'> </span>I know I can call <span
class=SpellE>pgDijkstra</span> multiple times to get the answer. The performance
of the solution is not good. Our goal is to calculate shortest paths of 100
cars to the same destination in less than a second. Calling <span class=SpellE>pgDijkstra</span>
100 times takes much, much more time than our goal.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Many, many thanks.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Fay<o:p></o:p></span></font></p>
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