Projections by Max Eckert-Greifendorff

[Catastrophe]

Please give me the forward and inverse formulas for the sphere and the ellipsoid (if any) of map projections presented by Max Eckert-Greifendorff. These include:

• Eckert I

• Eckert II

• Eckert III

• Eckert IV

• Eckert V

• Eckert VI

• Eckert-Greifendorff

[daan]

You can find forward definitions in Snyder’s An Album of Map Projections. Album does not supply inverses. Eckert’s original monograph might, though I do not have a copy of it. In any case, the inverses are simple to derive from the forward formulæ.

Best,
— daan