[GRASS-user] Oblique Equidistant Cylindrical / Equirectangular projection

[Morten Hulden]

On 07/13/2011 01:40 AM, Thomas Wootten wrote:
> I want to project some data into an Oblique Equidistant Cylindrical (AKA
> Equirectangular) projection. Proj.4 itself understands the following
> parameters string
>
> +proj=ob_tran +o_proj=eqc +o_alpha=315 +a=9213000 +b=9213000 +no_defs
> +units=m
>
> (Whether it actually gives the desired projection is another matter.
> Also the ellipsoid dimensions are funny because this is for a fictional
> extrasolar planet, not Earth.)
>
> But GRASS just gives "ERROR: Can't parse PROJ.4-style parameter string"
>
> How can I make this projection work in GRASS?

ob_tran has three possible ways of providing parameters. I think GRASS 
only supports the first one of these, i.e. latitude and longitude for 
the new pole.

# proj -l=ob_tran
   ob_tran : General Oblique Transformation
	Misc Sph
	o_proj= plus parameters for projection
	o_lat_p= o_lon_p= (new pole) or
	o_alpha= o_lon_c= o_lat_c= or
	o_lon_1= o_lat_1= o_lon_2= o_lat_2=