python - 尝试用反转的匹配捕获组替换与 pandas 数据框中的模式匹配的所有值

Question

这个问题已经有答案了:

Using regex matched groups in pandas dataframe replace function (2 个回答)

已关闭 6 年前。

一直在尝试用反转的匹配捕获组替换与 pandas 数据框中的模式匹配的所有值。所以Mouse, Mickey将替换为 Mickey Mouse

数据框看起来像:

+---+---------------+------+------+------+------+------+------+------+------+------+--+--+------+------+------+------+------+------+------+------+------+------+
|   |       0       |  1   |  2   |  3   |  4   |  5   |  6   |  7   |  8   |  9   |  |  |  15  |  16  |  17  |  18  |  19  |  20  |  21  |  22  |  23  |  24  |
+---+---------------+------+------+------+------+------+------+------+------+------+--+--+------+------+------+------+------+------+------+------+------+------+
| 0 | Mouse, Mickey | None | None | None | None | None | None | None | None | None |  |  | None | None | None | None | None | None | None | None | None | None |
| 1 | Duck, Donald  | None | None | None | None | None | None | None | None | None |  |  | None | None | None | None | None | None | None | None | None | None |
+---+---------------+------+------+------+------+------+------+------+------+------+--+--+------+------+------+------+------+------+------+------+------+------+

代码:

df.replace(r'(.*),\s+(.*)', r'\2 \1', inplace=True)

输出没有变化。我究竟做错了什么？谢谢!

Answer 1

您需要指定regex=True；默认情况下，DataFrame.replace 方法按字面替换值:

df = pd.DataFrame({"A": ["Mouse, Mickey", "Duck, Donald"]})

df.replace(r'(.*),\s+(.*)', r'\2 \1', inplace=True, regex=True)

df
#              A
#0  Mickey Mouse
#1  Donald Duck