[GRASS5] A problem with the proj library?

Roger Miller rgrmill at rt66.com
Sat Feb 9 12:07:00 EST 2002

On Saturday 09 February 2002 09:10, I wrote:

> pj_do_proj converts the input data from UTM to latlong (radians) using
> pj_inv then reprojects from latlong to Albers using pj_fwd.  The
> reprojection produces Albers coordinates in feet..   pj_do_proj divides the
> Albers coordinates by 0.3048 -- the "meters" constant from the PROJ_UNITS
> file for the Albers location.  That would be great if pj_fwd returned
> values in meters and I wanted the results converted to feet, but since
> pj_fwd returned values in feet the coordinates.
> I should be able to correct my results just by changing the "meters"
> constant in PROJ_UNITS to 1..  What I don't understand is how things
> changed so that a system that worked just over a month ago is broken now. 
> Any ideas?

I wrote this before I actually made the change in the "meters" constant.  I 
made that change and it didn't fix the problem, so my assessment above of the 
results from pj_do_proj is probably not right.  At least, that isn't the 
whole problem.

I'm still without a clue.

Roger Miller

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