[Proj] epsg parameters
Glynn Clements
glynn at gclements.plus.com
Wed Apr 2 16:15:45 EDT 2008
Paul Kelly wrote:
> I think it's in general a bad idea to include datum transformation
> information without any user interaction, because many users have the
> misconception that there is somehow a "correct" set of parameters which
> will always give them accurate results. When of course, as we've seen
> discussed on this list many times, accurate datum transformation is very
> much a localised thing: a transformation that gives accurate results in
> one region of a country may give very inaccurate results in another
> region, and a transformation that covers the whole country is in general
> not very accurate anywhere.
There's also the issue that being "accurate" may be less important
than being consistent with whatever data you're using.
--
Glynn Clements <glynn at gclements.plus.com>
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