from pylab import plot, log10, linspace, axis
from spectrum import *

AR, P, k = arburg(marple_data, 15)
PSD = arma2psd(AR, sides='centerdc')
plot(linspace(-0.5, 0.5, len(PSD)), 10*log10(PSD/max(PSD)))
axis([-0.5,0.5,-60,0])