Why are plots flipped when using freqz and comparing between Octave and SciPy?

When I plot response of these coefficients:

b=[1.01063287e+00, -1.46490341e+01,  9.94030209e+01, -4.19168764e+02, ...
  1.22949513e+03, -2.66000588e+03,  4.39112431e+03, -5.64225597e+03, ...
  5.70320516e+03, -4.55022454e+03,  2.85602975e+03, -1.39550096e+03, ...
  5.20372994e+02, -1.43160328e+02,  2.74037105e+01, -3.26098385e+00, ...
  1.81735269e-01];
a=[1.00000000e+00, -1.45159238e+01,  9.86464912e+01, -4.16614074e+02, ...
  1.22391361e+03, -2.65216678e+03,  4.38533779e+03, -5.64421414e+03, ...
  5.71487734e+03, -4.56742504e+03,  2.87187255e+03, -1.40575405e+03, ...
  5.25150201e+02, -1.44741759e+02,  2.77584882e+01, -3.30950845e+00, ...
  1.84797453e-01];

in Octave (which is OK):

pkg load signal
pkg load control

[h(:,1), w] = freqz(flip(b), flip(a),2048);
plot((w/pi),20*log10(abs(h(:,1))));

and in Python:

import matplotlib.pyplot as plt
import numpy as np
from scipy.signal import freqz

h = np.zeros(2048, float)
w = np.zeros(2048, float)

[h[:], w] = freqz(np.flip(b), np.flip(a), 2048)
  
plt.plot((w/np.pi),20*np.log10(h[:]));
plt.show()

, results are otherwise about equal but, as seen in plots, latter response is drawn something like twice turned compared to Octave's result.

What is going on and how to get equal plot with Octave from Python? I have tried by removing flip command from Python code but, response keeps being same.

Solution

scipy.signal.freqz returns (w,h), not (h,w) as you expect.

This should work:

w, h = freqz(np.flip(b), np.flip(a), 2048)

plt.plot(w/np.pi,20*np.log10(np.abs(h)))
plt.show()