[GRASS5] [bug #2537] (grass) aitoff/winkel tripel fails on rasters

[William K]

On Jul 24, 2004, at 2:18 PM, Glynn Clements wrote:

>
> William K wrote:
>
>> A question about the inverse projection thing - is that a PROJ
>> limitation, or a general limitation of the Aitoff/Winkel Tripel
>> projection?
>
> I'm not sure how to interpret that question.
>
> The proj library includes inverses for some projections, but not all,
> and not for Aitoff or Winkel Tripel.
>
> I suspect that these projections don't have a clearly defined inverse,
> i.e. the inverse can't be defined in terms of an algebraic expression,
> and there isn't a "standard" approximation.
>
I guess that's what I meant - whether PROJ chose not to include the 
inverse, or it's just not definable or available.  I'm thinking not 
included - though I haven't tried, the Arc docs don't say it isn't 
possible.  Maybe it's just difficult and ESRI spent the time (they 
certainly have the resources) to figure it out.

Oh well.

-----
William Kyngesburye <kyngchaos at charter.net>
http://webpages.charter.net/kyngchaos/

All generalizations are dangerous, even this one.