从df中按比例绘制一个随机子样本

import pandas as pd
import numpy as np
import matplotlib.pyplot as plt

data = {'A': np.random.randint(0, 100, 100),
        'B': np.random.randint(0, 100, 100),
        'C': np.random.randint(0, 100, 100)}
df = pd.DataFrame(data)

sample_ratio = 0.5  # 子样本比例为50%

sample = df.sample(frac=sample_ratio, random_state=42)

sample.plot(kind='bar')
plt.show()