[Proj] OSTN02 question: GRS80 instead of Airy.

[Roger Oberholtzer]

No takers on this one?

On Wed, 2006-10-25 at 12:58 +0200, Roger Oberholtzer wrote:
> I use the C API to do transformations. I am converting from GPS values
> in WGS84 to OSTN02 for the United Kingdom. My current code is:
> 
>        fromProj = pj_init_plus(
>                 "+proj=latlong "
>                 "+ellps=WGS84 "
>                 "+towgs84=0,0,0 "
>                 "+nodefs")
> 
>         toProj   = pj_init_plus(
>                 "+proj=tmerc "
>                 "+lat_0=49 "
>                 "+lon_0=-2 "
>                 "+k=0.9996012717 "
>                 "+x_0=400000 "
>                 "+y_0=-100000 "
>                 "+ellps=airy "
>                 "+nadgrids=gb.gsb "
>                 "+units=m "
>                 "+no_defs")
> 
> Note that I do a grid shift, using data provided by a kind member of
> this list.
> 
> My question is, how can I use the GRS80 ellipsoid instead of Airy? 
> 
> 
-- 
Roger Oberholtzer

OPQ Systems AB
Ramböll Sverige AB
Kapellgränd 7
P.O. Box 4205
SE-102 65 Stockholm, Sweden

Tel: Int +46 8-615 60 20
Fax: Int +46 8-31 42 23