Hii, I am using 'OutputFcn' to check integration values after each step. Druing my solution I want to stop integration after I reach y<=0. Problem I am acing is that, after each iteration solver returns me array of y which is correspond to a array of t rather than at each point of t. Thats why I am able to stop my integration but not at the point wherey<=0 but after some point. My code is as follows, function outfcn_test tspan = [0:.05:3]; options=odeset('OutputFcn',@getvalues); [t,y] = ode45(@myf,tspan,1,options); plot(t,y) function yprime = myf(t,y) yprime = -y-5*exp(-t)*sin(5*t); function status = getvalues(t,y,done) if y>=0 status = 0; else status =1; end I will appreciate any help in this regard. Thanks in advance.