demo_mi.py 文件源码

def plot_entropy():
    pylab.clf()
    pylab.figure(num=None, figsize=(5, 4))

    title = "Entropy $H(X)$"
    pylab.title(title)
    pylab.xlabel("$P(X=$coin will show heads up$)$")
    pylab.ylabel("$H(X)$")

    pylab.xlim(xmin=0, xmax=1.1)
    x = np.arange(0.001, 1, 0.001)
    y = -x * np.log2(x) - (1 - x) * np.log2(1 - x)
    pylab.plot(x, y)
    # pylab.xticks([w*7*24 for w in [0,1,2,3,4]], ['week %i'%(w+1) for w in
    # [0,1,2,3,4]])

    pylab.autoscale(tight=True)
    pylab.grid(True)

    filename = "entropy_demo.png"
    pylab.savefig(os.path.join(CHART_DIR, filename), bbox_inches="tight")