, , ; ax ax2, y
ax.yaxis.set_ticks_position("right")
ax2.yaxis.set_ticks_position("left")
import numpy as np
import matplotlib.pyplot as plt
a = range(1,10)
b = range(4,13)
ind = np.arange(len(a))
width = 0.65
fig = plt.figure()
ax = fig.add_subplot(111)
ax.bar(ind+width+0.35, b, 0.45, color='
ax2 = ax.twinx()
ax2.bar(ind+width, a, width, color='
ax.set_xticks(ind+width+(width/2))
ax.set_xticklabels(a)
ax.yaxis.set_ticks_position("right")
ax2.yaxis.set_ticks_position("left")
plt.tight_layout()
plt.show()

, , , align='center':
import numpy as np
import matplotlib.pyplot as plt
a = range(1,10)
b = range(4,13)
ind = np.arange(len(a))
fig = plt.figure()
ax = fig.add_subplot(111)
ax.bar(ind+0.25, b, 0.45, color='
ax2 = ax.twinx()
ax2.bar(ind, a, 0.65, color='
plt.xticks(ind, a)
ax.yaxis.set_ticks_position("right")
ax2.yaxis.set_ticks_position("left")
plt.tight_layout()
plt.show()
( , ).