Python中matplotlib如何绘制栈式直方图的示例

#!/usr/bin/env python# -*- coding: utf-8 -*-#http://www.jb51.net/article/100363.htm# numpy array intorduction#http://matplotlib.org/examples/statistics/histogram_demo_multihist.htmlimport numpy as npimport pylab as Pimport matplotlibd1=np.array([18.46,19.15,18.13 ,18.30 ,18.07 ,18.24 ,18.26 ,     17.14 ,18.44 ,18.06 ,17.44 ,16.57 ,16.34 ,17.21 ])d1=d1//1+(d1-d1//1)/0.6d2=np.array([19.33 ,19.06 ,18.10 ,17.55 ,19.55 ,19.13 ,18.54 ,     18.30 ,18.36 ,19.59 ,20.01 ,19.17 ,19.30 ,18.54 ,18.35 ,20.04 ])d2=d2//1+(d2-d2//1)/0.6d3=np.array([20.52 ,20.41 ,19.20 ,19.04 ,19.09 ,19.01 ,17.49 ,19.18 ,20.01 ,20.11 ])d3=d3//1+(d3-d3//1)/0.6d4=np.array([22.02 ,21.03,21.06 ,20.46 ,19.46 ,20.15 ,19.49 ,19.43 ,       19.51 ,19.39 ,19.33 ,19.18 ,19.13 ,19.22 ,18.46 ,19.07 ,       18.57 ,18.45 ,19.17 ,18.41 ,18.30 ])d4=d4//1+(d4-d4//1)/0.6x=([d1,d2,d3,d4])P.figure()#normed is False is goodn, bins, patches = P.hist(x, 12, [16.5, 22.5],normed=0, histtype='barstacked',              color=['blue', 'green', 'red','yellow'],             label=['   ', '   ', '   ','   '])print type(x)P.legend()#legend should be signed after set down the informationP.show()