python中pyplot直方图的绘制方式_python

import matplotlib.pyplot as plt
import numpy as np
from pylab import *         #支持中文
mpl.rcParams['font.sans-serif'] = ['SimHei']#SimHei中文黑体
np.random.seed(1)#设置随机种子
a=np.random.normal(100,20,size=100)#正态分布
plt.hist(a,20,normed=1,histtype='stepfilled',facecolor='g',alpha=0.8)
#上面的20为直方图的个数，normed=1表示归一化为概率，0的话就是在这个区间的个数，

plt.title('直方图')
plt.show()

import numpy as np
import matplotlib.pyplot as plt
from skimage import io
import cv2

if __name__ == '__main__':
    imgPath = 'background.png'
    img = io.imread(imgPath)
    n, bins, patches = plt.hist(img.flatten(), bins=256)
    plt.savefig("his.png")
    plt.show()