Examine prediction model and custom functions of `nlmpc`

object for
potential problems

`validateFunctions`

tests the prediction model, custom cost,
custom constraint, and Jacobian functions of a nonlinear MPC controller for potential
problems. When you first design your nonlinear MPC controller, or when you make significant
changes to an existing controller, it is best practice to validate your controller
functions.

`validateFcns(`

specifies nominal parameter values. If your controller has parameters, you must specify
`nlmpcobj`

,`x`

,`mv`

,`md`

,`parameters`

)`parameters`

.

When you provide your own analytical Jacobian functions, it is especially important that these functions return valid Jacobian values. If

`validateFunctions`

detects large differences between the values returned by your user-defined Jacobian functions and the finite-difference approximation, verify the code in your Jacobian implementations.

For each controller function, `validateFunctions`

checks whether the
function:

Exists on the MATLAB

^{®}pathHas the required number of input arguments

Can be executed successfully without errors

Returns the output arguments with the correct size and dimensions

Returns valid numerical data; that is, it does not return

`Inf`

or`NaN`

values

For Jacobian functions, `validateFunctions`

checks whether the returned
values are comparable to a finite-difference approximation of the Jacobian values. These
finite-difference values are computed using numerical perturbation.