PRACTICAL MATLAB® FOR ENGINEERS PRACTICAL MATLAB

Time Domain Representation of Continuous and Discrete Signals 65

figure(2);

ut35 = stepfun(t, 2) - stepfun(t, 3);

f5 = f2.*ut35;

t _ 1 = t+1;

f8 = f4 + ut35;

subplot(2,2,1);

plot(t, f5);

axis([1 4 -.1 .2]);

title(‘f5(t) vs t,(Example 1.7)’);

ylabel(‘f5(t)’); grid

subplot(2,2,2);

plot(t, f1+f3); axis([-6 6 -.5 1.5]);

title(‘f6(t) vs t,(Example 1.7)’);

ylabel(‘f5(t)’);grid

subplot(2,2,3);

plot(t _ 1, f5); axis([2 4 -.1 .25]);

title(‘f7(t) vs t,(Example 1.7)’);

ylabel(‘f5(t)’); xlabel(‘t’);;grid

subplot(2,2,4);

plot(t, f8); axis([-6 6 -1.2 1]);

title(‘f8(t) vs t,(Example 1.7)’);

ylabel(‘f5(t)’);xlabel(‘t’); grid

The resulting plots are shown in Figures 1.55 and 1.56.

FIGURE 1.55

Plots of f 1 (t), f 2 (t), f 3 (t), and f 4 (t) of Example 1.7.

f1(t) versus t, (Example 1.7)

f3(t) versus t, (Example 1.7)

f2(t) versus t, (Example 1.7)

f4(t) versus t, (Example 1.7)

1

1

200

150

100

50

0

0.5

0.5

0.5

−0.5

−0.5

−0.5

0

0

0

f1(t)

f3(t)

f2(t)

f4(t)

− 5

− 5

0 − 5

0

5 0

5

5

5

− 1

− 5 0

t t