AKDO/dial.py

import matplotlib.pyplot as plt
import mplcursors
import numpy as np
from numpy.fft import fft
from scipy.io import wavfile


def PowerSpectrum(y):
    Y = np.abs(fft(y))
    PS = Y[0:len(Y) // 2]
    df = fs / len(Y)
    f = np.arange(0, len(PS)) * df
    return f, PS


plt.clf()

fs, data = wavfile.read('dial.wav')

fig, axs = plt.subplots(2, num=1)

y = data[:, 0]
dt = 1 / fs
t = np.arange(0, len(y)) * dt

axs[0].plot(t, y)
axs[0].set_xlabel('t [s]')
axs[0].set_ylabel('y')

limits = [0.1, 0.45, 0.8, 1.2]

ss = limits[2]
se = limits[3]

to = t[(t > ss) & (t < se)]
yo = y[(t > ss) & (t < se)]

axs[0].plot(to, yo)

f, PS = PowerSpectrum(y)

fo, PSo = PowerSpectrum(yo)

axs[1].plot(f, PS)
axs[1].set_xlabel('f [Hz]')
axs[1].set_ylabel('Y abs')
axs[1].set_xlim(0, 1500)

axs[1].plot(fo, PSo)

mplcursors.cursor()

plt.show()