[GRASSLIST:2896] Re: g.region ellipsoid info

Paul Kelly paul-grass at stjohnspoint.co.uk
Wed Mar 10 15:19:42 EST 2004

On Wed, 10 Mar 2004, Martin du Saire wrote:

> Hi,
> I used g.setproj to adjust the ellipsoid info for my laea projection.  The
> new ellipsoid info was: sphere:6370997, but g.region -p shows
> ellipsoid: **unknown (default: WGS84)**

Don't worry about what g.region says. It should not really be reporting
the ellipsoid as it isn't relevant to the region settings.
Are you using the latest 5.3? I think I fixed some bugs
(e.g. it said the ellipsoid was unknown if there was no ellps line in the
PROJ_INFO when it is quite acceptable for it to be defined by the
underlying a, es etc. parameters)

> even though when I run g.setproj a second time the sphere info comes up as
> the current settings.  Is everything okay, or should I re-define the
> LOCATION from scratch?

If you post the output of g.projinfo here we can see if it is valid or not.

What modules are you using where the ellipsoid being a sphere might be
important? (converting to lat/long or reprojecting?) I don't think sphere
was handled very well in most 5.0.x versions---you may be better using 5.3
if necessary but I'm not 100% sure that everything that accepts a sphere
does so.

The main reason it was important was for people working with Mars but I
don't think I have seen any feedback from them about the bugfixes.

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