def derivativeY(self, x, y, z):
    '\n        Evaluate the first derivative with respect to y of the function at given\n        state space points.\n\n        Parameters\n        ----------\n        x : np.array\n             First input values.\n        y : np.array\n             Second input values; should be of same shape as x.\n        z : np.array\n             Third input values; should be of same shape as x.\n\n        Returns\n        -------\n        dfdy_out : np.array\n            First derivative of function with respect to the second input,\n            evaluated at (x,y,z), of same shape as inputs.\n        '
    (xShift, xShiftDer) = self.lowerBound.eval_with_derivative(y)
    dfdy_out = (self.func.derivativeY((x - xShift), y, z) - (xShiftDer * self.func.derivativeX((x - xShift), y, z)))
    return dfdy_out
Evaluate the first derivative with respect to y of the function at given
state space points.

Parameters
----------
x : np.array
     First input values.
y : np.array
     Second input values; should be of same shape as x.
z : np.array
     Third input values; should be of same shape as x.

Returns
-------
dfdy_out : np.array
    First derivative of function with respect to the second input,
    evaluated at (x,y,z), of same shape as inputs.
def derivativeY(self, x, y, z):
    '\n        Evaluate the first derivative with respect to y of the function at given\n        state space points.\n\n        Parameters\n        ----------\n        x : np.array\n             First input values.\n        y : np.array\n             Second input values; should be of same shape as x.\n        z : np.array\n             Third input values; should be of same shape as x.\n\n        Returns\n        -------\n        dfdy_out : np.array\n            First derivative of function with respect to the second input,\n            evaluated at (x,y,z), of same shape as inputs.\n        '
    (xShift, xShiftDer) = self.lowerBound.eval_with_derivative(y)
    dfdy_out = (self.func.derivativeY((x - xShift), y, z) - (xShiftDer * self.func.derivativeX((x - xShift), y, z)))
    return dfdy_out