<div dir="ltr">If you could output the data into some sort of useful format, including travel time and any other constraints, it might be fun to write an algorithm to solve it (or at the very least approximate an optimal solution.<div>
<br></div><div>Adi</div></div><div class="gmail_extra"><br><br><div class="gmail_quote">On 21 November 2013 09:13, Wesley Roberts <span dir="ltr"><<a href="mailto:wesley@biocarbonpartners.com" target="_blank">wesley@biocarbonpartners.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="white" lang="EN-ZA" link="blue" vlink="purple"><div><p class="MsoNormal"><span style="color:#1f497d">Thanks Gavin,</span></p><p class="MsoNormal"><span style="color:#1f497d"> </span></p>
<p class="MsoNormal"><span style="color:#1f497d">Ideally we want to use the time of travel to each of the plots so that we can select a number of representative plots during our validation that are not too far but that cover our entire study area. As such I will need to calculate distances from our conservation centre to each of the monitoring plots as if they were individual trips themselves.</span></p>
<p class="MsoNormal"><span style="color:#1f497d"> </span></p><p class="MsoNormal"><span style="color:#1f497d">W.</span></p><p class="MsoNormal"><span style="color:#1f497d"> </span></p><div><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";color:windowtext">From:</span></b><span lang="EN-US" style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext"> <a href="mailto:africa-bounces@lists.osgeo.org" target="_blank">africa-bounces@lists.osgeo.org</a> [mailto:<a href="mailto:africa-bounces@lists.osgeo.org" target="_blank">africa-bounces@lists.osgeo.org</a>] <b>On Behalf Of </b>Gavin Fleming<br>
<b>Sent:</b> 21 November 2013 09:10 AM</span></p><div><div class="h5"><br><b>To:</b> <a href="mailto:africa@lists.osgeo.org" target="_blank">africa@lists.osgeo.org</a><br><b>Subject:</b> Re: [OSGeo Africa] Routing application</div>
</div><p></p></div></div><div><div class="h5"><p class="MsoNormal">
</p><div><p class="MsoNormal">With a bit of Python you can automate routing tasks in any of these three environments. <br><br>It sounds like TSP (travelling salesman) would be a useful algorithm - find the shortest route to visit multiple sites in one journey. <br>
<br>On 21/11/2013 08:31, Wesley Roberts wrote:</p></div><blockquote style="margin-top:5.0pt;margin-bottom:5.0pt"><p class="MsoNormal"><span style="color:#1f497d">Many thanks Gavin,</span></p><p class="MsoNormal"><span style="color:#1f497d"> </span></p>
<p class="MsoNormal"><span style="color:#1f497d">I will look at the Road Graph option and then at Grass. We have over 300 locations so I would preferably like to automate the task.</span></p><p class="MsoNormal"><span style="color:#1f497d"> </span></p>
<p class="MsoNormal"><span style="color:#1f497d">Have been meaning to refine my PostGIS skills so ideally the pgRouting option might be my best option.</span></p><p class="MsoNormal"><span style="color:#1f497d"> </span></p>
<p class="MsoNormal"><span style="color:#1f497d">Regards,</span></p><p class="MsoNormal"><span style="color:#1f497d">Wesley</span></p><p class="MsoNormal"><span style="color:#1f497d"> </span></p><div><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";color:windowtext">From:</span></b><span lang="EN-US" style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext"> <a href="mailto:africa-bounces@lists.osgeo.org" target="_blank">africa-bounces@lists.osgeo.org</a> [mailto:<a href="mailto:africa-bounces@lists.osgeo.org" target="_blank">africa-bounces@lists.osgeo.org</a>] <b>On Behalf Of </b>Gavin Fleming<br>
<b>Sent:</b> 20 November 2013 06:02 PM<br><b>To:</b> <a href="mailto:africa@lists.osgeo.org" target="_blank">africa@lists.osgeo.org</a><br><b>Subject:</b> Re: [OSGeo Africa] Routing application</span></p></div></div><p class="MsoNormal">
</p><div><p class="MsoNormal">Hi Wesley<br><br>If it's just a few routes and you need to do the exercise just a few times then the Road Graph plugin in QGIS should do the trick. <br><br>If you need to do it more regularly and with more flexibility the pgRouting gives you tremendous power.<br>
<br>GRASS also has some really good routing functionality. <br><br>I've used all of the above and from the what you've described they will all provide the required information. <br><br>Gavin<br><br>On 20/11/2013 16:10, Wesley Roberts wrote:</p>
</div><blockquote style="margin-top:5.0pt;margin-bottom:5.0pt"><p class="MsoNormal">Dear Colleagues.</p><p class="MsoNormal"> </p><p class="MsoNormal">I have a quick question regarding a routing application I am trying to develop. </p>
<p class="MsoNormal"> </p><p class="MsoNormal">I would like to calculate travel time between a central location and a number of point locations (Permanent Monitoring Plots) along a sparse road network. The points do not occur on the roads. My travel time calculation is therefore made up of travel along roads (by car) and walking from the road to the point of interest. I can calculate distance from each point to the nearest road fairly easily, however, calculating the distance from each nearest point to a central location appears to a be a little more difficult. </p>
<p class="MsoNormal"> </p><p class="MsoNormal">Is this a job for pgRouting? I have found the following workshop and am happy to work through it provided the application can undertake the tasks I require (<a href="http://workshop.pgrouting.org/index.html" target="_blank">http://workshop.pgrouting.org/index.html</a>).</p>
<p class="MsoNormal"> </p><p class="MsoNormal">Does anyone on the list have experience using this software and will it provide the information I require? </p><p class="MsoNormal"> </p><p class="MsoNormal">Many thanks and kind regards,</p>
<p class="MsoNormal">Wesley</p><p class="MsoNormal"> </p><p class="MsoNormal"><img border="0" width="334" height="103" alt="Email_Signature"><span style="font-size:13.5pt"><br>
<br><span style="background:white">Wesley Roberts, PhD.</span><br><span style="background:white">Remote Sensing and GIS Specialist</span><br><span style="background:white">BioCarbon Partners</span><br><span style="background:white">Email: <a href="mailto:wes@biocarbonpartners.com" target="_blank">wes@biocarbonpartners.com</a></span><br>
<span style="background:white">Tel <a href="tel:%2B27%2083%20535%205646" value="+27835355646" target="_blank">+27 83 535 5646</a> (South Africa)</span> <br><span style="background:white"><a href="http://www.biocarbonpartners.com" target="_blank">www.biocarbonpartners.com</a></span></span></p>
<p class="MsoNormal"> </p>
<p class="MsoNormal" style="margin-bottom:12.0pt"><span style="font-size:12.0pt;font-family:"Times New Roman , serif","serif""><br><br></span></p><pre>_______________________________________________</pre>
<pre>Africa mailing list</pre><pre><a href="mailto:Africa@lists.osgeo.org" target="_blank">Africa@lists.osgeo.org</a></pre><pre><a href="http://lists.osgeo.org/mailman/listinfo/africa" target="_blank">http://lists.osgeo.org/mailman/listinfo/africa</a></pre>
</blockquote><p class="MsoNormal" style="margin-bottom:12.0pt"><span style="font-size:12.0pt;font-family:"Times New Roman , serif","serif""><br><br></span></p><pre>-- </pre><pre>Gavin Fleming</pre><pre>
t: 0218620670</pre><pre>w: 0218630660</pre><pre>c: 0845965680</pre><pre>f: 0866164820</pre><pre>Paarl</pre><pre>South Africa</pre><pre>18°59'19.6"E 33°44'46.1"S</pre><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""><br>
<br><br></span></p><pre>_______________________________________________</pre><pre>Africa mailing list</pre><pre><a href="mailto:Africa@lists.osgeo.org" target="_blank">Africa@lists.osgeo.org</a></pre><pre><a href="http://lists.osgeo.org/mailman/listinfo/africa" target="_blank">http://lists.osgeo.org/mailman/listinfo/africa</a></pre>
</blockquote><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""><br><br><br></span></p><pre>-- </pre><pre>Gavin Fleming</pre><pre>t: 0218620670</pre><pre>w: 0218630660</pre>
<pre>c: 0845965680</pre><pre>f: 0866164820</pre><pre>Paarl</pre><pre>South Africa</pre><pre>18°59'19.6"E 33°44'46.1"S</pre></div></div></div></div>
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