[Haskell-cafe] Abstraction in data types

Darrin Chandler dwchandler at stilyagin.com
Thu Mar 18 01:22:47 EDT 2010

On Wed, Mar 17, 2010 at 10:20:02PM -0700, Alexander Solla wrote:
> On Mar 17, 2010, at 9:56 PM, Alexander Solla wrote:
> >But your "spherical" points don't really form a basis in three-
> >space, or even over all of two-space.
> I'll take this back.  Lattitude and longitude is enough to "form a
> basis" on R^2, by taking a basis for the surface of the sphere in
> terms of latitude and longitude and projecting it stereographically.
> So if you wanted to use the normalization idea, you could use the
> stereographic projection formulas to turn a spherical point into a
> Cartesian point.
> http://en.wikipedia.org/wiki/Stereographic_projection

Yes. I believe other projections can be used as well (orthographic,

Darrin Chandler            |  Phoenix BSD User Group  |  MetaBUG
dwchandler at stilyagin.com   |  http://phxbug.org/      |  http://metabug.org/
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