#coding: utf-8
import matplotlib.pyplot as plt
import numpy as np
import itertools

def flip(items, ncol):
    return itertools.chain(*[items[i::ncol] for i in range(ncol)])

h = 0.5
# case-3, Case-2, case-1, dummy
x1 = np.array([54,46,46]) #Headrace
x2 = np.array([8,8,8]) #Headrace Surge tank
x3 = np.array([16,33,14]) #Penstock
x4 = np.array([43,43,37]) #Steel liner
x5 = np.array([16,16,25]) #Tailrace
x6 = np.array([0,0,4]) #Tailrace Surge Tank
x7 = np.array([86,86,100]) #PowerStation
x8 = np.array([11,13,14]) #Otheres
y = np.array([1,2,3])
sx1=x1
sx2=sx1+x2
sx3=sx2+x3
sx4=sx3+x4
sx5=sx4+x5
sx6=sx5+x6
sx7=sx6+x7
ax=plt.subplot(111) 
ax.barh(y,x1,color='red',               alpha=0.5,height=h,         label='Headrace',     align="center")
ax.barh(y,x2,color='red',   hatch=2*'x',alpha=0.5,height=h,left=sx1,label='Headrace S/T', align="center")
ax.barh(y,x3,color='yellow',            alpha=0.5,height=h,left=sx2,label='Penstock',     align="center")
ax.barh(y,x4,color='yellow',hatch=2*'/',alpha=0.5,height=h,left=sx3,label='Steel Pipe',   align="center")
ax.barh(y,x5,color='cyan',              alpha=0.5,height=h,left=sx4,label='Tailrace',     align="center")
ax.barh(y,x6,color='cyan',  hatch=2*'x',alpha=0.5,height=h,left=sx5,label='Tailrace S/T', align="center")
ax.barh(y,x7,color='green',             alpha=0.3,height=h,left=sx6,label='Power Station',align="center")
ax.barh(y,x8,color='pink',              alpha=0.5,height=h,left=sx7,label='Access etc.',  align="center")

handles, labels = ax.get_legend_handles_labels()
plt.legend(flip(handles,3),flip(labels,3),ncol=3,loc='center',bbox_to_anchor=(0.5, -0.4),shadow=True,prop={'size' : 15},handlelength=2,handleheight=0.8)
plt.subplots_adjust(bottom=0.40)
plt.xticks(range(0,300,50),fontsize=15)
plt.yticks(y, ['Case-3','Case-2','Case-1',''],fontsize=15)
plt.xlabel('Related Construction Cost (million US$)',fontsize=15)
plt.title('Comparison of Construction Cost',fontsize=20)
fnameF = "fig_bar3.png"
plt.savefig(fnameF)
plt.show()