function predatorprey

%parameters
epsilon=0.1;
%intervals of time which to run the model
tspan=[0 100];
%the initial condition for susceptible and infected
x0=[0.95; 0.05];

[t,x]=ode45(@f,tspan,x0);

plot(t,x(:,1),t,x(:,2),'linewidth',2);
xlabel('time');
ylabel('population');
legend('prey', 'predator'), pause

plot(x(:,1),x(:,2),'linewidth',2);
xlabel('prey');
ylabel('predator');

function dxdt=f(t,x)
dxdt=[x(1)*(1-epsilon*x(1)-x(2)); x(2)*(x(1)-1)];
end
end