import matplotlib.pyplot as plt

year=[1950,1970,1990,2010]

pop=[2.159,3.692,5.263,6.972]

plt.plot(year,pop)# X 列 和Y 列

plt.xlabel("Year")#X坐标

plt.ylabel("Population")#Y坐标

plt.title("World Population")#标题

plt.yticks([0,2,4,6,8],["0","2B","4B","6B","8B"])#刻度 表示是以万亿作为单位的



plt.show()

# values=[0,0.6,1.4,1.6,2.2,2.5,2.6,3.2,3.5,3.9,4.2,6]

# plt.hist(values,bins=4)