function yprime = repression(t,x,Z)
%
% This M-file examines a model for genetic control by repression
%
a1=2; a2=1; b1=1; b2=1; k=0.1; n=4;
x2del = Z(2,1);
xt1 = a1/(1+k*x2del^n)-b1*x(1);
xt2 = a2*x(1)-b2*x(2);
yprime = [xt1;xt2];
% sol=dde23(ddefcn, lags, history, tspan);
% sol=dde23(@repression,[2],[1,1],[0,20]);
% sol.x t-values sol.y y-values
%