jacobian to calculate the gradient of a real m-vector valued function with real n-vector argument.
hessian to calculate the Hessian (second derivative) of a scalar real valued function with real n-vector argument.
genD to calculate the gradient and second derivative of a real m-vector valued function with real n-vector argument.
Maintainer: Paul Gilbert
Fornberg and Sloan, (1994) Acta Numerica, p. 203-267; Table 1, page 213)