来自按级别分组的多索引pandas数据帧的子图

import pandas as pd
import matplotlib.pyplot as plt

# 创建多索引数据框
data = {'A': [1, 2, 3, 4, 5, 6],
        'B': [7, 8, 9, 10, 11, 12],
        'C': [13, 14, 15, 16, 17, 18]}
index = pd.MultiIndex.from_tuples([('Group1', 'Subgroup1'), ('Group1', 'Subgroup2'),
                                   ('Group2', 'Subgroup1'), ('Group2', 'Subgroup2'),
                                   ('Group3', 'Subgroup1'), ('Group3', 'Subgroup2')])
df = pd.DataFrame(data, index=index)

# 按级别分组
grouped = df.groupby(level=0)

# 绘制子图
fig, axes = plt.subplots(len(grouped), 1, figsize=(8, 6), sharex=True)
for i, (name, group) in enumerate(grouped):
    group.plot(ax=axes[i], kind='bar', title=name)

plt.tight_layout()
plt.show()