[postgis-users] Create new lines from GPS points

[Ralf Suhr]

This will work. The GPS point is never on the road geometry.

ST_Line_Substring( road, 
  ST_Line_Locate_Point(road, ST_ClosestPoint(gps_start, road)),
  ST_Line_Locate_Point(road, ST_ClosestPoint(gps_end, road))
) AS highlight

Gr
Ralf

Am Dienstag 11 Januar 2011, 18:08:29 schrieb Ralf Suhr:
> Hi Martin.
> 
> ST_Line_Substring(road, ST_Line_Locate_Point(road, gps_start),
> ST_Line_Locate_Point(road, gps_end)) AS highlight
> 
> Gr
> Ralf
> 
> Am Dienstag 11 Januar 2011, 17:46:06 schrieb Martin Fafard:
> > Ralf
> > 
> > Yes, ok for the buffer. But how to "dynamically segment" my new road
> > from my original segment?
> > 
> > Martin
> > 
> > Ralf Suhr a écrit :
> > > Hi Martin,
> > > 
> > > you will not get a correct solution for this problem. Your road network
> > > and the gps points differs always.
> > > 
> > > A possible "solution" is building a buffer around the streets und look
> > > für intersection with gps points and filter by direction road/points.
> > > Grouping gps points can give you the start and end point for the road.
> > > If a road is only one times driven.
> > > 
> > > Gr
> > > Ralf
> > > 
> > > Am Dienstag 11 Januar 2011, 17:16:18 schrieb Martin Fafard:
> > >> Hi
> > >> 
> > >> I have a network of roads (topological) and I receive GPS points. I
> > >> would like to create new lines who follow exactly the same path as my
> > >> road from the GPS points (to "highlight" where the GPS unit was on the
> > >> network). The problem is I need to segment the new line because the
> > >> GPS points can stop anywhere on my roads... Any advice to do this?
> > >> Thank you
> > >> 
> > >> Martin F
> > >> _______________________________________________
> > >> postgis-users mailing list
> > >> postgis-users at postgis.refractions.net
> > >> http://postgis.refractions.net/mailman/listinfo/postgis-users

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