Hi, I have some considerable difficulty with the following problem:
I have a LINESTRING table with walking tracks
I have a MULTILINESTRING table with contours (with elevation attribute).
I can successfully get the points of intersection between tracks and contours
to obtain the elevation and coordinates at the point of intersection.
What I need to do next, and I don't know how, is to merge the points of
intersection for a given track with the track linestring, i.e. add the
intersection points to the track linestring (or create a new track which
includes the intersection points). However the intersection points have to be
inserted in the right position in the track linestring, not just at the front,
as ST_LINEMERGE() seems to do. The reason is I need then to traverse the track,
point by point, to obtain the distance between points.
Any suggestions will be most welcome, thank you.
George
_______________________________________________
postgis-users mailing list
[email protected]
http://postgis.refractions.net/mailman/listinfo/postgis-users
