pub trait DifferentiableVectorFunction<T>: VectorFunction<T>where
T: Scalar,{
// Required method
fn solve_jacobian_system(
&mut self,
sol: &mut DVectorViewMut<'_, T>,
x: &DVectorView<'_, T>,
rhs: &DVectorView<'_, T>,
) -> Result<(), Box<dyn Error>>;
}