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Re: IDL 8.1 Map Projections [message #77817] Fri, 07 October 2011 06:36
David Fanning is currently offline  David Fanning
Messages: 11724
Registered: August 2001
Senior Member
nata writes:

> You should know that the max and min latitude on the Mercator
> projection is ±85.05113°. That's why you don't see anything on the
> poles....
> http://en.wikipedia.org/wiki/Mercator_projection

Yes, maybe so. But why cut things off at 75 degrees
then? There is a lot about these map projections that
seem really arbitrary (and undocumented) to me.
I don't understand, for example, why the aspect
ratios of the map projections in the graphics window
are what they are. I presume there *is* a reason,
but I just can't find it anywhere.

Cheers,

David


--
David Fanning, Ph.D.
Fanning Software Consulting, Inc.
Coyote's Guide to IDL Programming: http://www.idlcoyote.com/
Sepore ma de ni thui. ("Perhaps thou speakest truth.")
Re: IDL 8.1 Map Projections [message #77818 is a reply to message #77817] Fri, 07 October 2011 06:28 Go to previous message
natha is currently offline  natha
Messages: 482
Registered: October 2007
Senior Member
You should know that the max and min latitude on the Mercator
projection is ±85.05113°. That's why you don't see anything on the
poles....
http://en.wikipedia.org/wiki/Mercator_projection

nata
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