[GRASS-user] Raster and shape files miss aligned.

[Hamish]

Michael wrote:
> My guess is that the projection information for one of the
> original files is incorrect. My bet is on the shapefile. You
> can test by importing a 3rd file where you know the
> projection info is good (e.g., something from USGS or an
> SRTM) and seeing which one matches and which one doesn't.

specifically check that the datum is set correctly.

a correct projection but wrong datum typically shows up as a
roughly 100m north-south misalignment, as the ellipsoid is less
or more squashed from the poles to the equator in one vs the
other.
(here I use "datum" and "ellipsoid" interchangably, while
technically in grass a given datum implies its given ellipsoid)


Hamish