from pylab import pi, log10, randn, plot
import scipy.signal
from spectrum import pburg

# Define AR filter coefficients
a = [1, -2.2137, 2.9403, -2.1697, 0.9606];

[w,H] = scipy.signal.freqz(1, a, 256)
Hp = plot(w/pi, 20*log10(2*abs(H)/(2.*pi)),'r')
x = scipy.signal.lfilter([1], a, randn(256))
p = pburg(x, 4, sampling=2)
p()
p.plot()