【python常用函数】——小波变换

// An highlighted block
t = np.arange(0, len(x_f)/fs, 1/fs)
wavename = 'morl'
totalscal = 2000
fc = pywt.central_frequency(wavename)
cparam = 2 * fc * totalscal
scales = cparam / np.arange(totalscal, 1, -1)

[cwtmatr, frequencies] = pywt.cwt(x_f, scales, wavename, 1.0 / fs)
# fig
plt.figure(figsize=(20, 10))
plt.contourf(t, frequencies, abs(cwtmatr))
plt.ylabel('hz')
plt.xlabel('s')
plt.subplots_adjust(hspace=0.4)
plt.show()

连续小波变换中可用的小波：
**A wide range of continous wavelets are now available. These include the following:**
	Gaussian wavelets (gaus1…``gaus8``)
	Mexican hat wavelet (mexh)
	Morlet wavelet (morl)
	Complex Gaussian wavelets (cgau1…``cgau8``)
	Shannon wavelet (shan)
	Frequency B-Spline wavelet (fbsp)
	Complex Morlet wavelet (cmor)

参考链接: pywavelets文档.