User`s guide

step
11-220
11step
Purpose Step response of LTI systems
Syntax step(sys)
step(sys,t)
step(sys1,sys2,...,sysN)
step(sys1,sys2,...,sysN,t)
step(sys1,'PlotStyle1',...,sysN,'PlotStyleN')
[y,t,x] = step(sys)
Description step calculates the unit step response of a linear system. Zero initial state is
assumed in thestate-space case. Wheninvokedwithnooutput arguments,this
function plots the step response on the screen.
step(sys) plots the step response of an arbitrary LTI model sys.Thismodel
can be continuous or discrete, and SISO or MIMO. T he step response of
multi-input systems is the collection of step responses for each input channel.
The duration of simulation is determined automatically based on the system
poles and zeros.
step(sys,t) sets the simulation horizon explicitly. You can specify either a
final time
t = Tfinal (in seconds), or a vector of evenly spaced time samples
of the form
t = 0:dt:Tfinal
For discrete system s, the spacin g dt should match the sample period. For
continuous systems,
dt beco mes the samp le t ime of the discret ized simulation
model (see “Algorithm”), so make sure to choose
dt small enough to capture
transient phenomena.
To plot th e step r espo nses of se ve ral L TI m o dels
sys1,..., sysN on a si n gle
figure, use
step(sys1,sys2,...,sysN)
step(sys1,sys2,...,sysN,t)