erf top-level property
Returns an approximation of the error function defined as:
erf(x) = 2/sqrt(pi) * integral(from: 0, to: x, exp(-t * t), dt)
Compared to the approximation provided by gnuplot the maximum
error is 1.5e-15
for x > 1.0
and 4.0e-16
for x in [-1, 1]
.
Implementation
final erf = MemoizedFunction(_erf);