python 画 roc曲线图

实现代码参考:

from sklearn.metrics import roc_curve, auc
import numpy as np
from sklearn import metrics

import matplotlib.pyplot as plt


y = np.array([1,1,0,1,1,1,0,0,1,0,1,0,1,0,0,0,1,0,1,0])
scores = np.array([0.9, 0.8, 0.7, 0.6,0.55,0.54,0.53,0.52,0.51,0.505,0.4,0.39,0.38,0.37,0.36,0.35,0.34,0.33,0.30,0.1])
fpr, tpr, thresholds = metrics.roc_curve(y, scores, pos_label=1)
print("fpr",fpr)
print("tpr",tpr)
print("thresholds",thresholds)
auc = metrics.auc(fpr, tpr)

plt.figure()
lw = 2
plt.plot(fpr, tpr, color='darkorange',
         lw=lw, label='ROC curve (area = %0.2f)' % auc)
plt.plot([0, 1], [0, 1], color='navy', lw=lw, linestyle='--')
plt.xlim([0.0, 1.0])
plt.ylim([0.0, 1.05])
plt.xlabel('False Positive Rate')
plt.ylabel('True Positive Rate')
plt.title('Receiver operating characteristic example')
plt.legend(loc="lower right")
plt.show()

 

绘制结果如下:

python 画 roc曲线图