import numpy as np
import matplotlib.cm as cm
from matplotlib.pyplot import figure, show, rc, savefig

fig = figure(figsize=(8,8))
ax = fig.add_axes([0.1, 0.1, 0.8, 0.8], polar=True)

N = 20
theta = np.arange(0.0, 2*np.pi, 2*np.pi/N)
radii = np.arange(1,N+1)/2.0
width = np.ones(N)/4.0

##### 1 #####
ax.bar(theta, radii, width=width, bottom=0.5)
#############

##### 2 #####
#bars = ax.bar(theta, radii, width=width, bottom=0.5)

#for r,bar in zip(radii, bars):
#    bar.set_facecolor(cm.jet(r/10.))
#    bar.set_alpha(0.5)
#############
show()
