Generation of Linear Time Vector from ODE45

Good Greetings

I'm working on a code that involves usage of ode45 solver. As far as i can see, 'time' vector is automatically generated by ode45. I'm only providing the first and the last point of time vector, not the step size. The problem is, time vector generated is not linear. I'm providing the link of the plot of time vector which clearly shows my concern.

https://docs.google.com/leaf?id=0B4dPcFFHHl9VOTZkZDVhZWEtNjJhNi00NzYxLTkwN2YtNWU2ZWM2YjFkZDY0&hl=en_US&authkey=CJGEv_kO

Kindly suggest me some suitable reason and solution for my problem.

Thanks and Regards.

Chirag Goel

Answer 1

[Fangjun Jiang]

That is not strange. By default, ode45 solver uses variable step size. If you want to fix the step size, you might be able to do it by specifying the 'InitialStep' and 'MaxStep' the same value.

[TOUT,YOUT] = ODE45(ODEFUN,TSPAN,Y0,OPTIONS)

help odeset to see all the options.