Specifications

3 Operations on LTI Models
3-26
Resampling of Discrete-Time Models
You can resample a discrete-time TF, SS, or ZPK model sys1 by typing
sys2 = d2d(sys1,Ts)
The new sampling period Ts doesnothavetobeanintegermultipleofthe
original sampling period. For example, typing
h1 = tf([1 0.4],[1 –0.7],0.1);
h2 = d2d(h1,0.25);
resamples h1 at the sampling period of 0.25 seconds, rather than 0.1 seconds.
You can compare the step responses of
h1 and h2 by typing
step(h1,'--',h2,'-')
The resulting plot is shown on the figure below (h1 is the dashed line).