how to plotting bar on matplotlib

1import matplotlib.pyplot as plt
2fig = plt.figure()
3ax = fig.add_axes([0,0,1,1])
4langs = ['C', 'C++', 'Java', 'Python', 'PHP']
5students = [23,17,35,29,12]
6ax.bar(langs,students)
7plt.show()

1import matplotlib.pyplot as plt 
2
3data = [5., 25., 50., 20.]
4plt.bar(range(len(data)),data)
5plt.show()
6
7// to set the thickness of a bar, we can set 'width'
8// plt.bar(range(len(data)), data, width = 1.)