[Proj] Jacobi + Guyou projection; conformal map of ellipsoid to sphere

Charles Karney charles.karney at sri.com
Tue Dec 30 14:35:08 EST 2014

I've updated my notes on Jacobi's conformal projection of a triaxial
ellipsoid; see


New stuff:

* the limits, ellipsoid of revolution and sphere, are easily obtained;

* the Guyou projection (and hence the Peirce quincuncial projection) are
   special cases of Jacobi's projection (which predates both of these);

* Jacobi + Guyou can be used to map a triaxial ellipsoid conformally
   onto a sphere.


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