pub fn newton_method<F, Func>(
f: &Func,
x0: ArrayView1<'_, F>,
tol: F,
max_iter: usize,
) -> (Array1<F>, bool)pub fn newton_method<F, Func>(
f: &Func,
x0: ArrayView1<'_, F>,
tol: F,
max_iter: usize,
) -> (Array1<F>, bool)