A minimum phase wavelet

minimum_phase.py

from scipy.signal import remez, minimum_phase
import matplotlib.pyplot as plt

# Based on this example from the scipy docs:
# https://docs.scipy.org/doc/scipy/reference/generated/scipy.signal.minimum_phase.html
freq = [0, 0.2, 0.3, 1.0]
desired = [1, 0]
h_linear = remez(151, freq, desired, Hz=2.0)
h_min_hil = minimum_phase(h_linear, method='hilbert')

fig, axs = plt.subplots(ncols=2, figsize=(12, 4), facecolor='w', sharey=True)
axs[0].plot(h_linear)
axs[0].set(xlim=[0, len(h_linear) - 1], ylabel='Amplitude', xlabel='Samples')
axs[0].axhline(0, c='k', alpha=0.25, lw=1.25)
axs[0].grid(c='k', alpha=0.15)
axs[0].set_title('Zero phase')
axs[1].plot(h_min_hil, c='C1')
axs[1].set(xlim=[0, len(h_linear) - 1], xlabel='Samples')
axs[1].axhline(0, c='k', alpha=0.25, lw=1.25)
axs[1].grid(c='k', alpha=0.15)
axs[1].set_title('Minimum phase')
plt.tight_layout()