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I have been asked to find the shortest route from a particular start point to multiple properties along our shires road network. In QGIS I have tested the different network analysis tools and other plugins but I cannot find one that allows you to include multiple stops along a road network. I can only include a start and end point.

Is there such a plugin that allows for this?

2 Answers 2

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I would recommend using the Travelling salesman algorithm for this one.

This has been implemented using the Grass Plugin, which can be found under v.net.salesman.

There is further reading here https://grass.osgeo.org/grass78/manuals/v.net.salesman.html

and also some other discussion Creating input node file for V.net.salesman in GRASS?

Your input vector line will be your roads and your property points being nodes. It also offers some nice options in case the property points are not 'on' the network.

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  • Thanks for that. I'll take a look this week.
    – Josh
    Commented Aug 11, 2021 at 2:26
  • I have this working for two lots of data after cleaning up the network data. One still doesn't work and the network looks fine and points sit on the road. I see the node that can't be reached is also sitting at the same location as another node. Should this work if two nodes are at the same location?
    – Josh
    Commented Oct 7, 2021 at 6:01
  • oooo good question. Id imagine its smart enough to ignore overlapping points? But I am guessing........However that means that only one of the addresses would be reported upon. Suggest that - if this is valid use case and data - setting up a relationship in the database between geometry and addresses. ie: One node may have multiple addresses. Salesman tool can navigate along the geometry points, then once you have them, then you can use some SQL or joined attributes to the join table, to retrieve the actual text address details.
    – nr_aus
    Commented Oct 7, 2021 at 6:13
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    I seem to have fixed it. I did move the point on the road through a prior SQL stored procedure, but then snapped to the network again in Grass. I replaced the SQL part with just the property centroid and it works. Mind you, the list of properties changes weekly so that problem may still be lurking. I'll keep an eye on it.
    – Josh
    Commented Oct 11, 2021 at 21:00
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I suggest you use ORS tools plugin in QGIS and perform Traveling Salesman analysis. To use ORS tools you will need API key that you can get for free here.

For good introduction to ORS tools, watch this video.

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  • Thanks for that. I'll take a look this week.
    – Josh
    Commented Aug 11, 2021 at 2:26

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