DTFT, DFT, ZT, and FFT 507
0.5
1
1.5
2
2.5
DTFT [0.6n u(n)] using freqz
Magnitude
− 4 − 3 − 2 − 1 0 1 2 3 4
− 1
−0.5
0
0.5
1
frequency W in rad.
− 4 − 3 − 2 −1 0123 4
frequency W in rad.
Phase in rad.
FIGURE 5.19
DTFT of f(n) using freqz of Example 5.1.
FIGURE 5.20
Error evaluation (parts b and c) of Example 5.1.
0
5
10
Magnitude error
Amplitude
− 4 − 3 − 2 − 1 0 1 2 3 4
− 4 − 3 − 2 − 101234
− 2
− 1
− 5
0
1
2
× 10 −^16
× 10 −^16
frequency W in rad.
Phase error
Phase in rad.