混淆矩阵，上面带有已分类/分类错误的实例数(Python/Matplotlib) [英] Confusion Matrix with number of classified/misclassified instances on it (Python/Matplotlib)

问题描述

我正在使用matplotlib使用以下代码绘制混淆矩阵:

I am plotting a confusion matrix with matplotlib with the following code:

from numpy import *
import matplotlib.pyplot as plt
from pylab import *

conf_arr = [[33,2,0,0,0,0,0,0,0,1,3], [3,31,0,0,0,0,0,0,0,0,0], [0,4,41,0,0,0,0,0,0,0,1], [0,1,0,30,0,6,0,0,0,0,1], [0,0,0,0,38,10,0,0,0,0,0], [0,0,0,3,1,39,0,0,0,0,4], [0,2,2,0,4,1,31,0,0,0,2], [0,1,0,0,0,0,0,36,0,2,0], [0,0,0,0,0,0,1,5,37,5,1], [3,0,0,0,0,0,0,0,0,39,0], [0,0,0,0,0,0,0,0,0,0,38] ]

norm_conf = []
for i in conf_arr:
    a = 0
    tmp_arr = []
    a = sum(i,0)
    for j in i:
        tmp_arr.append(float(j)/float(a))
    norm_conf.append(tmp_arr)

plt.clf()
fig = plt.figure()
ax = fig.add_subplot(111)
res = ax.imshow(array(norm_conf), cmap=cm.jet, interpolation='nearest')
cb = fig.colorbar(res)
savefig("confmat.png", format="png")

但是我想让混淆矩阵像这样的图形在其上显示数字(右图).如何在图形上绘制conf_arr?

But I want to the confusion matrix to show the numbers on it like this graphic (the right one). How can I plot the conf_arr on the graphic?

推荐答案

您可以使用

You can use text to put arbitrary text in your plot. For example, inserting the following lines into your code will write the numbers (note the first and last lines are from your code to show you where to insert my lines):

res = ax.imshow(array(norm_conf), cmap=cm.jet, interpolation='nearest')
for i, cas in enumerate(conf_arr):
    for j, c in enumerate(cas):
        if c>0:
            plt.text(j-.2, i+.2, c, fontsize=14)
cb = fig.colorbar(res)

这篇关于混淆矩阵，上面带有已分类/分类错误的实例数(Python/Matplotlib)的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！