Minor Description
Background for those who aren't familiar: math libs like Math and FastMath have two mysterious methods, log1p and expm1. log1p
= log(1+x) and expm1 = exp-1 mathetmatically, but can return a correct answer even when x was small, where floating-point error due to the addition/subtraction introduces a relatively large error.
There are three instances in the code that can employ these specialized methods and gain a measurable improvement in accuracy. See patch and tests for an example – try the tests without the code change to see the error.