散点图

import numpy as np
import matplotlib.pyplot as plt

n=1024

X=np.random.normal(0,1,n)   #生成n个均值0，方差1的随机数据
Y=np.random.normal(0,1,n)

T=np.arctan2(Y,X)   #for color value，对应color map

plt.scatter(X,Y,s=75,c=T,alpha=0.5) #alpha透明度

##plt.scatter(np.arange(5),np.arange(5))

plt.xlim((-1.5,1.5))
plt.ylim((-1.5,1.5))

plt.xticks(())    #隐去刻度值
plt.yticks(())

plt.show()

运行结果

import numpy as np
import matplotlib.pyplot as plt

n=1024

plt.scatter(np.arange(5),np.arange(5))

plt.xticks(())
plt.yticks(())

plt.show()

运行结果

柱状图

import numpy as np
import matplotlib.pyplot as plt

n=12

X=np.arange(n)
Y1=(1-X/float(n))*np.random.uniform(0.5,1.0,n)
Y2=(1-X/float(n))*np.random.uniform(0.5,1.0,n)

plt.bar(X,+Y1,facecolor='#9999ff',edgecolor='white')
plt.bar(X,-Y2,facecolor='#ff9999',edgecolor='white')

for x,y in zip(X,Y1):
    #ha:horizontal alignment
    #va:vertial alignment
    plt.text(x+0.04,y+0.05,'%.2f'%y,ha='center',va='bottom')

for x,y in zip(X,Y2):
    #ha:horizontal alignment
    #va:vertial alignment
    plt.text(x+0.04,-y-0.05,'-%.2f'%y,ha='center',va='top')

plt.xlim(-0.5,n)
plt.xticks(())
plt.ylim(-1.25,1.25)
plt.yticks(())

plt.show()

image.png

等高线contour


import matplotlib.pyplot as plt
import numpy as np

def f(x,y):
    # the height function
    return (1 - x / 2 + x**5 + y**3) * np.exp(-x**2 -y**2)

n = 256
x = np.linspace(-3, 3, n)
y = np.linspace(-3, 3, n)
X,Y = np.meshgrid(x, y)

# use plt.contourf to filling contours
# X, Y and value for (X,Y) point
plt.contourf(X, Y, f(X, Y), 3, alpha=.75, cmap=plt.cm.hot)

# use plt.contour to add contour lines
C = plt.contour(X, Y, f(X, Y), 8, colors='black', linewidth=.5)
# adding label
plt.clabel(C, inline=True, fontsize=10)

plt.xticks(())
plt.yticks(())
plt.show()