www.gusucode.com > control 案例程序 matlab源码代码 > control/TimeDomainResponsesofDiscreteTimeModelExample.m

    %% Time-Domain Responses of Discrete-Time Model  
% This example shows how to obtain a step-response plot and step-response
% data for a discrete-time dynamic system model. Obtaining time-domain
% responses of discrete-time models is the same as for continuous-time
% models, except that the time sample points are limited by the sample time
% |Ts| of the model.
%
% You can use the techniques of this example with commands such as |impulse|,
% |initial|, |impulseplot|, and |initialpot| to obtain time-domain responses
% of discrete-time models. 

%% 
% Create a discrete-time transfer function model and plot its response to
% a step input at $t$ = 0. 
H = tf([-0.06,0.4],[1,-1.6,0.78],0.1);
step(H)    

%%
% For discrete-time models, |step| plots the response at multiples of
% the sample time, assuming a hold between samples.  

%% 
% Compute the step response of |H| between 0.5 and 2.5 seconds. 
[y,t] = step(H,0.5:0.1:2.5); 

%%
% When you specify a time vector for the response of a discrete-time model,
% the time step must match the sample time |Ts| of the discrete-time model.
% The vector |t| contains the time points between 0.5 and 2.5 seconds, at
% multiples of the sample time of |H|, 0.1 s. The vector |y| contains the
% corresponding step response values.