python画出混淆矩阵
时间: 2023-08-31 14:09:15 浏览: 160
以下是Python代码,用于绘制混淆矩阵:
```python
import matplotlib.pyplot as plt
import numpy as np
def plot_confusion_matrix(cm, classes, normalize=False, title='Confusion matrix', cmap=plt.cm.Blues):
"""
This function prints and plots the confusion matrix.
Normalization can be applied by setting `normalize=True`.
"""
if normalize:
cm = cm.astype('float') / cm.sum(axis=1)[:, np.newaxis]
print("Normalized confusion matrix")
else:
print('Confusion matrix, without normalization')
print(cm)
plt.imshow(cm, interpolation='nearest', cmap=cmap)
plt.title(title)
plt.colorbar()
tick_marks = np.arange(len(classes))
plt.xticks(tick_marks, classes, rotation=45)
plt.yticks(tick_marks, classes)
fmt = '.2f' if normalize else 'd'
thresh = cm.max() / 2.
for i, j in product(range(cm.shape[0]), range(cm.shape[1])):
plt.text(j, i, format(cm[i, j], fmt),
horizontalalignment="center",
color="white" if cm[i, j] > thresh else "black")
plt.ylabel('True label')
plt.xlabel('Predicted label')
plt.tight_layout()
# 示例:
# 混淆矩阵数据
cm = np.array([[10, 2, 3],
[1, 9, 2],
[3, 2, 10]])
# 类别标签
classes = ['Class A', 'Class B', 'Class C']
# 绘制混淆矩阵
plot_confusion_matrix(cm, classes)
```
运行以上代码,将得到一个混淆矩阵的可视化结果。可以通过调整`cm`和`classes`参数来适应你的实际数据。
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