Function modified_newton_solve 

pub fn modified_newton_solve<F, Func>(
    f: Func,
    x0: Array1<F>,
    jac_manager: &mut JacobianManager<F>,
    params: NewtonParameters<F>,
) -> IntegrateResult<NewtonResult<F>>
where
    F: IntegrateFloat + Default,
    Func: Fn(&Array1<F>) -> Array1<F>,

Modified Newton solve that reuses the same Jacobian for multiple iterations