Signal Resampling (downsampling / upsampling)

The most popular/common functions are:

1. scipy.signal.resample 
2. scipy.signal.resample_poly

from scipy import signal
x = np.linspace(0, 10, 20, endpoint=False)
y = np.cos(-x**2/6.0)

f_fft = signal.resample(y, 100)
f_poly = signal.resample_poly(y, 100, 20, padtype='line')  # same as "signal.resample_poly(y, 5, 1, padtype='line')"

xnew = np.linspace(0, 10, 100, endpoint=False)


import matplotlib.pyplot as plt
plt.figure(figsize=(10, 4))
plt.plot(xnew, f_fft, 'b.-', xnew, f_poly, 'r.-')
plt.plot(x, y, 'ko-')
plt.plot(10, y[0], 'bo', 10, 0., 'ro')  # boundaries
plt.legend(['resample', 'resamp_poly', 'data'], loc='best')
plt.tight_layout()
plt.show()

 

References

[1] dsp.stackexchange.com/questions/62228/downsample-signal-to-a-specific-number-of-samples-in-python?newreg=d2b8d30f4cca47b39053b0a73336c5f3