You can use the event function to trigger an external event:
Opt = odeset('Events', @yourEvent);
t0 = 0;
tEnd = 1000;
y0 = [0,0];
Param = 17;
while t0 < tEnd
yourFcn = @(t,y) yourFcn(t, y, Param);
[time, pos] = ode45(yourFcn, [t0, tEnd], y0, Opt);
t0 = time(end);
y0 = pos(end, :);
Param = ??? % Adjust the parameter like you want.
end
And your event function:
function [value, isterminal, direction] = yourEvent(t, y)
persistent P
if nargin == 0
P = 1;
return;
end
drawnow;
if isempty(P)
value = 0;
isterminal = 0;
direction = 0;
else
value = -1;
isterminal = 1;
direction = 0;
P = [];
end
end
Now ODE45 calls yourEvent with 2 inputs every time. But you can call this function from a timer callback also without input arguments. Then the persistent variable P is used as a flag, which stops the integration in the next time step. This allows the main loop while t0<tEnd to modify the parameters used inside the function to be integrated, or maybe the current velocities or positions.
The drawnow is important, because without it, Matlab does not evaluate the other callbacks.
