extractive variables to files

[Jim Maas]

Apologies for syntax questions here. I have googled and made attempts 
.... still no luck!

Ben has helped me get an initial script to run, will list it at bottom. 
Could someone show me how to

  1. extract the values of the variables "ca" and "out" such that I can
     store them in a data file with their appropriate independent
     values of "t" ?
  2. plot the same values of "ca" and "out" vs "t"/
  3. What does the "@" sign stand for here ...I've dug around and
     googled both octave and matlab and can't find it!

Thanks

Jim

%-----------------------------------------------------------------------
% File mmsolve script file
% Demonstrate how to single pool model using ODE
% Call ODE45
% Dr. Jim Maas
% 19/03/09
%-----------------------------------------------------------------------

% Read/assign model parameters -----------------------------------------
vmax = 36.79;
km = 0.22;
sz = 115.0;
qin = 18.63;

% Initial values -------------------------------------------------------
qa0=25.0;

% Auxillary Equations---------------------------------------------------

dqadt = @(t,y)(qin - qaout(t,y,vmax,km,sz));

function [out,ca] = qaout(t,y,vmax,km,sz)
ca = y/sz;
out = vmax/(1+km/ca);
endfunction

% Call a routine to solve ODE ------------------------------------------

[t, y] = ode45 (dqadt, [0:0.1:10], qa0); %Octave

% print/plot results ---------------------------------------------------
plot(t,y);
xlabel('TIME'); ylabel('QUANTITY');

----
Jim Maas