a=1;
m=.02;
n=.01;
Kh=10;
Kt=100;
f=0.6667;
P=110;
al=.05;
b=3;
tau=4;
c=.05;
de=3;
g=1;

history = [9; 1; 0.1];
tspan = [0, 60]; 
opts = ddeset('RelTol',1e-5,'AbsTol',1e-8);

% Solve equation
sol = dde23('tumor1', tau, history, tspan, opts,a,m,n,Kh,P,al,b,c,de,f,g,Kt);

plot(sol.x, sol.y);
legend('healthy cells mass (kg)', 'tumor cells mass (10 gm)', 'tumor microvessels mass (10 gm)',2);
text(1,26,'P_e=P-1000nx-10my-10nz','FontSize',10)
text(1,24,'x\prime=amin(1,P_e/(1000fk_hn))x-ax((x+0.01y)/k_h)','FontSize',10)
text(1,22,'y\prime=by(min(1,P_e/(1000fkhm)))min(1,gmax(0,z-\alphay))-y/K_t)','FontSize',10)
text(1,20,'z\prime=cy(t-\tau)-\deltaz^2/y','FontSize',10)
text(1,17,'a=1, m=.02, n=.01, K_h=10, K_t=100, f=0.6667','FontSize',10)
text(1,15,'P=110, \alpha=.05, b=3, \tau=4, c=.05, \delta=3, g=1','FontSize',10)
text(1,13,'(x(0), y(0), z(0))=(9, 1, 0.1)','FontSize',10)
title('Figure 8. Homogeneous tumor growth with small g value');
xlabel('time t (days)');
ylim([0 35]);
ylabel('x, y, z');