Tobler’s Hyperelliptical projection

Waldo R. Tobler’s family of hyperelliptical projections is available for d3-geo-projection as pull request #133.

You can try the following parameters:

Default:

• d3.geoHyperelliptical().alpha(0).gamma(1.183136).k(2.5) (fig. 9)

Values described in Tobler, “The Hyperelliptical and Other New Pseudo Cylindrical Equal Area Map Projections”, Journal of Geophysical Research, 1973:

• d3.geoHyperelliptical().alpha(0).gamma(6).k(1/2) (fig. 5)
• d3.geoHyperelliptical().alpha(1/4).gamma(1.194).k(2) (fig. 6)
• d3.geoHyperelliptical().alpha(1/2).gamma(Math.PI/2).k(2) (fig. 7)
• d3.geoHyperelliptical().alpha(0).gamma(1.461).k(3/2) (fig. 8)