Inverse hyperbolic cosine.
(Quaternion overloading of standard MATLAB® function)
Y = acosh(X)
acosh(X) computes the inverse hyperbolic cosine of its argument, which must be a real quaternion (acosh is not yet implemented for complexified quaternions).
This function is computed using the Matlab® function of the same name by first computing an isomorphic complex number. The result is then assigned the same quaternion axis as the original argument.