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Find your nearest spot on STRtree

I use nettopologysuite (port . I use the SRTtree implementation to store a list of time zones and corresponding coordinates (based on this sentence). I took a list of cities from geonames, pulled out the city’s time zone and coordinates, and I store them in STRtree. Problem with which I’m facing is that this implementation doesn’t provide the “closest” function. To execute the request, I have to specify the starting point and the circle. Currently I am increasing the circle by .1 in the loop until I find some results and then I take first is there any better first way to do this?

That's what I'm doing:

public static SRTtree Cities { get; set; } public static string GetTimezone(double lat, double lng) { var envelope = new Envelope(new Coordinate(lat, lng)); IList results; do { envelope.ExpandBy(.1); results = Cities.Query(envelope); } while (results.Count == 0); return results[0] as string; }
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2 answers

JTS 1.13 provides the STRTree.nearestNeighbor method for this operation. I don't know if this has been ported to NTS yet, but if not possible, you can request it.

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If the only query you need to complete is Get Your Nearest Place, using R-Tree might not be the best choice. I could think of two alternatives:

  • Calculate the distance to each place using the Garveyne formula and find the minimum distance. If you have too many coordinates, this might be the best solution. See " Finding proximity " for more information.
  • Use a data structure that allows you to search for the nearest coordinates, such as KD-Tree . Please note that the KD-Tree implementation in NetTopologySuite is not suitable for your use.
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