function yp = lotka(t,y)
%LOTKA  Lotka-Volterra predator-prey model.

%   Copyright 1984-2000 The MathWorks, Inc. 
%   $Revision: 5.5 $  $Date: 2000/06/01 03:46:39 $

yp = diag([1 - .01*y(2), -1 + .02*y(1)])*y;
