Create a ticket describing the calibration, that's useful info and would be a good utility for LRS users for a future version.
P. 2012/3/28 Andrés Maneiro <amane...@icarto.es>: > Hello people, > > I'm reviewing what postgis is able to do in terms of Linear Referencing. As > fas as I could see, to calibrate a linestring there is only the method > ST_AddMeasure: > http://www.postgis.org/docs/ST_AddMeasure.html > > So, as stated in the example, the operation will create a route like: > > SELECT ST_AsEWKT(ST_AddMeasure( > ST_GeomFromEWKT('LINESTRING(1 0, 2 0, 4 0)'),1,4)) As ewelev; > ewelev > -------------------------------- > LINESTRINGM(1 0 1,2 0 2,4 0 4) > > What I'm wondering is if somehow I could calibrate the vertex of the > linestring, having as a result, for example, this route: > > LINESTRINGM(1 0 1,2 0 *1.7*,4 0 4) > > The project I'm working on is related to road management, and it's very > common that the ratio between a route's length and its measures is not > constant. So, my doubt goes: is it somehow possible to create a route in > postgis where the measure and the distance are not directly related? > > (For those who know how ArcGIS "dynamic segmentation" works, what I'd like > to achive is something similar to calibrate a route using points [1]). > > Let me know if I explain myself properly. > > best, > Andrés > > [1] > http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/About_calibrating_route_measures_using_points/00390000000t000000/ > _______________________________________________ > postgis-users mailing list > postgis-users@postgis.refractions.net > http://postgis.refractions.net/mailman/listinfo/postgis-users _______________________________________________ postgis-users mailing list postgis-users@postgis.refractions.net http://postgis.refractions.net/mailman/listinfo/postgis-users