用python的Matplotlib库画散点图、气泡图和箱线图

1. 散点图

• 方法一：用plt.scatter()函数

import matplotlib.pyplot as plt
import numpy as np

x = np.linspace(0.05, 10, 50)
y = np.sin(x)

a = np.random.randn(100)
b = np.random.randn(100)
plt.scatter(a,b, color = 'c')
plt.show()

• plt.scatter()的其他参数设置

import matplotlib.pyplot as plt
import numpy as np

x = np.linspace(0.05, 10, 50)
y = np.sin(x)

a = np.random.randn(100)
b = np.random.randn(100)
sValue = a * 3                                              # 不同大小
cValue = ['r','orange','yellow','g','b','c','purple']       # 不同颜色
lValue = x                                                  # 不同线宽
plt.scatter(a,b, c = cValue ,s = sValue, linewidth = lValue, marker = 'o')
plt.show()

有种小孩涂鸦的感觉，是不是要好看很多，嘻嘻嘻

• 方法二：其实也可以用plt.plot()函数

import matplotlib.pyplot as plt
import numpy as np

x = np.linspace(0.05, 10, 5)
y = np.sin(x)

a = np.random.randn(100)
b = np.random.randn(100)
plt.plot(a,b, 'c.')
plt.show()

2. 气泡图

可以用散点图的函数（plt.scatter()），只需改变参数即可得到散点图

import matplotlib.pyplot as plt
import numpy as np

x = np.linspace(0.05, 10, 10)
y = x * 2

sValue = x * 3                                             # 不同大小,随着x增大而变大
cValue = ['r','orange','yellow','g','b','c','purple']      # 不同颜色
lValue = sValue                                            # 不同线宽

plt.scatter(x,y, c = cValue ,s = sValue*10, linewidth = lValue, marker = 'o')
plt.xlim(0,12)
plt.ylim(0,25)
plt.show()

3. 箱线图

• 用plt.boxplot()函数

import matplotlib.pyplot as plt
import numpy as np

x = np.linspace(0.05, 10, 50)
y = np.sin(x)

a = np.random.randn(100)
b = np.random.randn(100)
plt.boxplot([a, b, x, y]) 
plt.show()

• plt.boxplot()的其他参数设置

import matplotlib.pyplot as plt
import numpy as np

x = np.linspace(0.05, 10, 50)
y = np.sin(x)

a = np.random.randn(100)
b = np.random.randn(100)
plt.boxplot([a, b, x, y],
           notch = 1,     # =1 中间凹陷; =0 正常，系统默认为0，像瘦版的箱线图
           sym = 'b+',    # 异常值显示符号
           vert = 0       # =0 为横向; =1 为纵向 ，系统默认为1
          ) 
plt.show()