Chapter 4: Programming in Matlab - College of the Redwoods

Section 4.2 Control Structures in Matlab 319
(a)
Figure 4.7.
(b)
Generating a square wave with mod.
Let’s make one last adjustment, increasing the amplitude by 2, then shifting the
graph downward 1 unit. This produces the square wave shown in Figure 4.8.
y=2*y-1;
plot(t,y,’*’)
Figure 4.8. A square
wave with period 2.
Note that this square waves alternates between the values 1 and −1. The curve
equals 1 on the first half of its period, then −1 on its second half. This pattern
then repeats with period 2 over the remainder of its domain.
Fourier Series. Using advanced mathematics, it can be shown that the
following Fourier Series “converges” to the square wave pictured in Figure 4.8
∞∑ 4
sin(2n + 1)πt (4.4)
(2n + 1)π
n=0