[GRASS-dev] Missing projections

[Glynn Clements]

Maciej Sieczka wrote:

> > The following projections are listed by "proj -lp" but don't have
> > entries in proj-parms.table:
> > 
> > 	geos : Geostationary Satellite View
> > 	lcca : Lambert Conformal Conic Alternative
> > 	sterea : Oblique Stereographic Alternative
> > 	vitk1 : Vitkovsky I
> > 
> > Can anyone provide the necessary parameter information, i.e. which
> > PROJ parameters they accept, and what (if any) default value should be
> > used?
> 
> I know some about sterea. It accepts exactly the same parameters as
> stere.

Looking at the PROJ source code, sterea doesn't accept any additional
parameters, whereas stere accepts lat_ts=.

stere is defined as:

STERE:Stereographic:KFACT=ask,1.0;LAT0=ask,0.0;LATTS=ask,0.0;LON0=ask,20.0

For sterea, I'd assume that the KFACT=1 and LAT0=0 defaults are
probably reasonable.

I'm not sure where the LON0 default comes from; of 121 projections,
119 accept LON0 (UPS and UTM are the exceptions), and 100 of those
have 20 as the default.

So, I'll add this for sterea:

STEREA:Oblique Stereographic Alternative:KFACT=ask,1.0;LAT0=ask,0.0;LON0=ask,20.0

-- 
Glynn Clements <glynn at gclements.plus.com>