EE341.01: MATLAB M-FILE FOR PLOTTING STEP FUNCTIONS WITH SUBPLOT COMMAND

This example shows a MATLAB M-file for plotting step functions in three horizontal regions of the graphics window.

%
% M-File Name: example3.m
%
% Description:  M-file to divide the graphics window into three
%               horizontal regions and plot a step function in each.
%

clear                             % clear all variables from workspace
clf                               % clear figures

%****************************************************************************
% Create the first step function

t0 = -2.0:0.01:-0.01;             % define u(t)=0, -2<=t<=-.01
u0 = zeros(size(t0));
t1 = 0:0.01:3;                    % define u(t)=1, 0<=t<=3
u1 = ones(size(t1));
t = [t0 t1];                      % create t and u(t)
u = [u0 u1];         

subplot(3,1,1)                    % divide graphics region into 3 rows and
                                  % 1 column - put first plot in region 1

plot(t,u)                         % plot solid step function

grid                              % add grid and labels to plot
xlabel('t(s)')
ylabel('u(t)')
title('Step Function')

%****************************************************************************
% Create the second step function

t0 = -2.0:0.01:0.99;              % define u(t-1)=0, -2<=t<=.99
u0 = zeros(size(t0));
t1 = 1.0:0.01:3;                  % define u(t-1)=1, 1<=t<=3
u1 = ones(size(t1));
t = [t0 t1];                      % create t and u(t)
u = [u0 u1];         

subplot(3,1,2)                    % divide graphics region into 3 rows and
                                  % 1 column - put second plot in region 2

plot(t,u,'--')                    % plot dashed step function 

grid                              % add grid and labels to plot
xlabel('t(s)')
ylabel('u(t-1)')
title('Step Function Shifted Right')

%****************************************************************************
% Create the third step function

t0 = -2.0:0.01:-1.01;             % define u(t+1)=0, -2<=t<=-1.01
u0 = zeros(size(t0));
t1 = -1.0:0.01:3;                 % define u(t+1)=1, -1<=t<=3
u1 = ones(size(t1));
t = [t0 t1];                      % create t and u(t)
u = [u0 u1];         

subplot(3,1,3)                    % divide graphics region into 3 rows and
                                  % 1 column - put third plot in region 3

plot(t,u,'-.')                    % plot dash-dot step function 

grid                              % add grid and labels to plot
xlabel('t(s)')
ylabel('u(t+1)')
title('Step Function Shifted Left')