使用Pandas数据帧中布尔列的组合计数创建一个方阵

import pandas as pd
import numpy as np

df = pd.DataFrame({'A': [True, False, True, False],
                   'B': [True, True, False, False],
                   'C': [False, True, False, True]})

matrix = np.zeros((len(df.columns), len(df.columns)), dtype=int)
for i, col1 in enumerate(df.columns):
    for j, col2 in enumerate(df.columns):
        matrix[i, j] = sum(df[col1] & df[col2])