Specifications

step
16-216
All systems must have the same number of inputs and outputs but may
otherwise be a mix of continuous- and discrete-time systems. This syntax is
useful to compare the step responses of multiple systems.
You can also specify a distinctive color, linestyle, and/or marker for each
system. For example,
step(sys1,'y:',sys2,'g--')
plots the step response of sys1 with a dotted yellow line and the step response
of
sys2 with a green dashed line.
When invoked with output arguments,
[y,t] = step(sys)
[y,t,x] = step(sys) % for state-space models only
y = step(sys,t)
return the output response y, the time vector t used for simulation, and the
state trajectories
x (for state-space models only). No plot is drawn on the
screen. For single-input systems,
y hasasmanyrowsastimesamples(length
of
t), and as many columns as outputs. In the multi-input case, the step
responses of each input channel are stacked up along the third dimension of
y.
The dimensions of
y are then
and
y(:,:,j) gives the response to a unit step command injected in the jth
input channel. Similarly, the dimensions of
x are
Example Plot the step response of the following second-order state-space model.
length of
t()
number of outputs
()
number of inputs
()××
length of
t()
number of states
()
number of inputs
()××
x
·
1
x
·
2
0.5572– 0.7814–
0.7814 0
x
1
x
2
11–
02
u
1
u
2
+=
y
1.9691 6.4493
x
1
x
2
=