"""

The new ticker code was designed to explicitly support user customized

ticking. The documentation

http://matplotlib.org/matplotlib.ticker.html details this

process. That code defines a lot of preset tickers but was primarily

designed to be user extensible.

In this example a user defined function is used to format the ticks in

millions of dollars on the y axis

"""

from matplotlib.ticker import FuncFormatter

import matplotlib.pyplot as plt

import numpy as np

x = np.arange(4)

money = [1.5e5, 2.5e6, 5.5e6, 2.0e7]

def millions(x, pos):

'The two args are the value and tick position'

return '$%1.1fM' % (x*1e-6)

formatter = FuncFormatter(millions)

fig, ax = plt.subplots()

ax.yaxis.set_major_formatter(formatter)

plt.bar(x, money)

plt.xticks(x + 0.5, ('Bill', 'Fred', 'Mary', 'Sue'))

plt.show()