Comparisons with absolute epsilons are usually useful when comparing
numbers to zero, for non-zero numbers it's advised to switch to relative
epsilons instead to obtain meaningful results (check [1] for more
details).

The new API introduces approxEqAbs and approxEqRel, where the former
aliases and deprecated the old `approxEq`, allowing the user to pick the
right tool for the job.

The documentation is meant to guide the user in the choice of the
correct alternative.

[1] https://randomascii.wordpress.com/2012/02/25/comparing-floating-point-numbers-2012-edition/