On Sat, 15 Jun 2019 at 03:32, Nicolas Cadieux <[email protected]> wrote: > I am trying to get the length of a line in python. (Not just the straight > length between the first and last nodes). Using geopandas, (therefore the > Shapely lib) I am getting the euclidien distance even though the dataframe > holdings the line geometries has a CRS (WGS84, zone UTM 18 S). Obviously, > the WGS84 Ellipsoid is not taken into account. > > Can I do this with gdal/ogr?
If you are looking for a really precise length (~15 nm) on WGS84, you can use the Python version of GeographicLib [1]. Note that PROJ incorporates the C library for Geodesics from GeographicLib [2], and that this is also the same method used in PostGIS (since version 2.2). I'm not sure how SpatiaLite has implemented ST_Length, but could be worth checking into. [1] https://geographiclib.sourceforge.io/html/python/ [2] https://proj.org/geodesic.html#solution-of-geodesic-problems _______________________________________________ gdal-dev mailing list [email protected] https://lists.osgeo.org/mailman/listinfo/gdal-dev
