`DERIVF`

can be nested to compute partial derivatives of any order:
$$\frac{\partial}{\partial z}\frac{\partial}{\partial y}\frac{\partial}{\partial x}f\left(x,y,z\right)$$

Consider the partial derivative:

$\frac{\partial}{\partial y}\frac{\partial}{\partial x}cos(x,y)=-sin\left(xy\right)-xycos\left(xy\right)$

We compute the partial derivative of `cos(xy)` at `(π,π)` by nesting `DERIVF`

and compare the result with the analytical value shown in `B3` below:

A | |

1 | =COS(X1*Y1) |

2 | =DERIVF(B1,X1,PI()) |

3 | =DERIVF(B2,Y1,PI()) |

⇒

A | B | |

1 | 1 | |

2 | 0 | |

3 | 9.3394486379 | 9.3394486379 |