This module provides an interface to a number of mathematical functions.
A collection of mathematical functions that return floats. Arguments are numbers.
Returns the error function of X, where:
erf(X) = 2/sqrt(pi)*integral from 0 to X of exp(-t*t) dt.
erfc(X) returns 1.0 - erf(X), computed by methods that avoid cancellation for large X.
A useful number.
As these are the C library, the same limitations apply.