为pandas中堆叠水平条形图的值添加批注

import pandas as pd
import matplotlib.pyplot as plt

data = {'A': [10, 15, 20],
        'B': [5, 8, 12],
        'C': [12, 10, 15]}
df = pd.DataFrame(data)

ax = df.plot.barh(stacked=True)

for i, patch in enumerate(ax.patches):
    width = patch.get_width()
    height = patch.get_height()
    x = patch.get_x()
    y = patch.get_y()
    
    # 计算批注文本的位置
    annotation_x = x + width / 2
    annotation_y = y + height / 2
    
    # 添加批注文本
    ax.annotate(f'{width:.1f}', (annotation_x, annotation_y),
                ha='center', va='center')

ax.set_title('Stacked Horizontal Bar Chart')
ax.set_xlabel('Value')
ax.set_ylabel('Category')

plt.show()