%function prob_7_4()
% 
% Written by:
% -- 
% John L. Weatherwax                2006-05-21
% 
% email: wax@alum.mit.edu
% 
% Please send comments and especially bug reports to the
% above email address.
% 
%-----

addpath( '../../Code' ); 

[xout,yout]=ode23tx( @prob_7_4_fn, [0,2], [0] ); 
figure; 
subplot(2,1,1); 
plot( xout, yout, 'xr' ); hold on; 
plot( xout, erf(xout), 'og' ); 
subplot(2,1,2); 
plot( xout, yout-erf(xout), 'xb' );