Inverse hyperbolic tangent
atanh
In y=atanh(x), for real elements of x outside the domain [-1,1], the complex part of Scilab y value is the opposite of Matlab y value.
y = atanh(2) y = 0.5493 + 1.5708i
y = atanh(2) y = 0.5493061 - 1.5707963i
