DTFT, DFT, ZT, and FFT 545
0 10 20 30 40 50
0
5
10
15
20
abs[fft(gf(n))]
abs[fft(gf(n))] versus k
0 10 20 30 40 50
− 4
− 2
0
2
4
angle[fft(gf(n))] versus k
angle[fft(gf(n))]
0 10 20 30 40 50
0
5
10
15
20
abs[fft(gc(n))] versus k
index k
abs[fft(gc(n))]
0 10 20 30 40 50
− 4
− 3
− 2
− 1
0
angle[fft(gc(n))] versus k
index k
angle[fft(gc(n))]
FIGURE 5.58
Magnitude and phase plots of fft[gf (n)] and fft[gc(n)], over the range 1 ≤ k ≤ 50 of Example 5.13.
0 5 10 15 20 25 30 35 40 45 50
−0.5
0
0.5
error plots in time and frequency
Amplitude
− (^1005101520253035404550)
− 10
10
0
Magnitude error
0 5 10 15 20 25 30 35 40 45 50
0
10
phase error
index k
index n
error = g(n)
∠error(k) = ∠DFT[gf(n)] - ∠DFT[gf(n)]
error = DFT[g(n)
FIGURE 5.59
Error plots in the time and frequency domains of Example 5.13.