ABSTRACT

Yn+1 = Yn + I1t In (7.104) Applying the explicit Euler method to the model ODE, ji + aji = 0, for which J(t, ji) = -aji, gives

I G=(I-a!1t) I For stability, IGI ::s 1. Thus,

-I ::s (I - a I1t) ::s 1

(7.105)

(7.106)

(7.107) The right-hand inequality is always satisfied for a I1t 2: 0. The left-hand inequality is satisfied only if

(7.108)

which requires that !1t ::s 2/a. Consequently, the explicit Euler method is conditionally stable.