%
% Written by:
% --
% John L. Weatherwax                2009-04-21
%
% email: wax@alum.mit.edu
%
% Please send comments and especially bug reports to the
% above email address.
%
%-----

% EPage 103
% 

close all; clc; clear all; 

addpath('../../BookCode');

K_1 = 2;
K_2 = 10;
C = 0.001;
D = 0.002; 

S_1 = 1.2;
S_2 = S_1; 

y0 = [ 5000; 100 ];
fprime = @(t,x) ( [ K_1 * x(1) - C * x(1) * x(2) - S_1 * x(1) ; -K_2 * x(2) + D * x(1) * x(2) - S_2 * x(2) ] );

[t,x] = ode23( fprime, [0, 10], y0 );

plot( t, x, '-' ); 
grid('on');
xlabel('time'); ylabel('preditor/prey population values');

%saveas( gcf, '../../WriteUp/Graphics/Chapter5/c_5_p_7_plot.eps', 'epsc' );