Huang solves ⃗ x = A⃗ x using diagonalization; but in and the present study, matrix exponential is employed to simplify programming. For sake of description of an exact solution to a problem in section 4, supplied here is the broader solution of the inhomogeneous system ⃗ x = A⃗ x + ⃗ f (t) where ⃗ f (t) is n × 1 column vector function (it will merely be a constant vector in what follows):