Torben Jansen

Ref.: John P. Snyder, “Magnifying-Glass” Azimuthal Map Projections, The American Cartographer, 14:1 (1987), 61-68. http://dx.doi.org/10.1559/152304087783875318 Reference implementation: https://observablehq.com/@toja/magnifying-glass-projections

Nicolosi Globular - outer hemisphere seems to be broken

1

According to *Snyder/Voxland, An Album of Map Projections, p. 234*, the sign in https://github.com/OSGeo/proj.4/blob/master/src/PJ_nocol.c#L43 should take "the opposite sign of φ times the sign of b" (`tb` in your code)....

regressionExponential and regressionPower break for negative y values

2

Probably because of `Math.log(dy)` that will return `NaN`