如何对Pandas DataFrame的gen列按A/B值对排序并格式化？

原始数据定义 #

import pandas as pd
df1 = pd.DataFrame( {'st': {0: 1, 1: 0, 2: 2, 3: 0, 4: 1, 5: 5, 6: 0, 7: 7, 8: 19, 9: 0, 10: 0, 11: 0, 12: 3, 13: 0}, 'gen': {0: 'B1', 1: 'A0,B0', 2: 'A1,B1', 3: 'A0,B0', 4: 'B109', 5: 'B4,A1', 6: 'A0,B0', 7: 'A4,B3', 8: 'B15,A4', 9: 'A0,B0', 10: 'A0,B0', 11: 'A0,B0', 12: 'A123', 13: 'A0,B0'}, 'gen2': {0: 'B(1)', 1: 'A(0),B(0)', 2: 'A(1),B(1)', 3: 'A(0),B(0)', 4: 'B(109)', 5: 'A(1),B(4)', 6: 'A(0),B(0)', 7: 'A(4),B(3)', 8: 'A(4),B(15)', 9: 'A(0),B(0)', 10: 'A(0),B(0)', 11: 'A(0),B(0)', 12: 'A(123)', 13: 'A(0),B(0)'}} )

期望输出 #

st  gen     gen2
0   1   B1      B(1)
1   0   A0,B0   A(0),B(0)
2   2   A1,B1   A(1),B(1)
3   0   A0,B0   A(0),B(0)
4   1   B109    B(109)
5   5   B4,A1   A(1),B(4)
6   0   A0,B0   A(0),B(0)
7   7   A4,B3   A(4),B(3)
8   19  B15,A4  A(4),B(15)
9   0   A0,B0   A(0),B(0)
10  0   A0,B0   A(0),B(0)
11  0   A0,B0   A(0),B(0)
12  3   A123    A(123)
13  0   A0,B0   A(0),B(0)

需求说明 #

• 对gen列中逗号分隔的元素排序：确保以A开头的元素排在以B开头的元素之前；
• 格式化每个元素：将元素中的数字部分放入括号，最终生成gen2列的样式（示例：B4,A1转为A(1),B(4)，B15,A4转为A(4),B(15)）。

实现代码 #

import re

def process_gen(s):
    # 拆分逗号分隔的元素
    parts = s.split(',')
    # 按首字母排序，A在前B在后
    sorted_parts = sorted(parts, key=lambda x: x[0])
    # 格式化每个元素：字母+括号包裹数字
    formatted_parts = []
    for part in sorted_parts:
        match_result = re.match(r'([AB])(\d+)', part)
        if match_result:
            letter, num_str = match_result.groups()
            formatted_parts.append(f"{letter}({num_str})")
    return ','.join(formatted_parts)

# 应用函数到gen列，生成gen2
df1['gen2'] = df1['gen'].apply(process_gen)

# 查看结果
print(df1)

内容的提问来源于stack exchange，提问作者josepmaria