polars.Expr.str.replace_many#

Expr.str.replace_many(patterns: IntoExpr | Mapping[str, str], replace_with: IntoExpr | NoDefault = <no_default>, *, ascii_case_insensitive: bool = False) → Expr[source]#

使用Aho-Corasick算法替换多个匹配项。

Parameters:

patterns: 用于搜索和替换的字符串模式。接受表达式输入。字符串被解析为列名，其他非表达式输入被解析为字面量。还接受模式到其替换的映射，作为replace_many(pl.Series(mapping.keys()), pl.Series(mapping.values()))的语法糖。
replace_with: 替换模式匹配的字符串。接受表达式输入。非表达式输入被解析为字面量。长度必须与patterns的长度匹配或长度为1。这可以广播，因此支持多对一和多对多。
ascii_case_insensitive: 启用ASCII感知的大小写不敏感匹配。当此选项启用时，搜索将仅对ASCII字母（a-z和A-Z）不区分大小写。

注释

此方法仅支持字符串字面量的匹配，不支持正则表达式匹配。

示例

通过向patterns和replace_with参数传递等长的序列来替换多个模式。

>>> _ = pl.Config.set_fmt_str_lengths(100)
>>> _ = pl.Config.set_tbl_width_chars(110)
>>> df = pl.DataFrame(
...     {
...         "lyrics": [
...             "Everybody wants to rule the world",
...             "Tell me what you want, what you really really want",
...             "Can you feel the love tonight",
...         ]
...     }
... )
>>> df.with_columns(
...     pl.col("lyrics")
...     .str.replace_many(
...         ["me", "you"],
...         ["you", "me"],
...     )
...     .alias("confusing")
... )
shape: (3, 2)
┌────────────────────────────────────────────────────┬───────────────────────────────────────────────────┐
│ lyrics                                             ┆ confusing                                         │
│ ---                                                ┆ ---                                               │
│ str                                                ┆ str                                               │
╞════════════════════════════════════════════════════╪═══════════════════════════════════════════════════╡
│ Everybody wants to rule the world                  ┆ Everybody wants to rule the world                 │
│ Tell me what you want, what you really really want ┆ Tell you what me want, what me really really want │
│ Can you feel the love tonight                      ┆ Can me feel the love tonight                      │
└────────────────────────────────────────────────────┴───────────────────────────────────────────────────┘

通过向replace_with参数传递一个字符串或长度为1的序列，广播替换多个模式。

>>> _ = pl.Config.set_fmt_str_lengths(100)
>>> df = pl.DataFrame(
...     {
...         "lyrics": [
...             "Everybody wants to rule the world",
...             "Tell me what you want, what you really really want",
...             "Can you feel the love tonight",
...         ]
...     }
... )
>>> df.with_columns(
...     pl.col("lyrics")
...     .str.replace_many(
...         ["me", "you", "they"],
...         "",
...     )
...     .alias("removes_pronouns")
... )
shape: (3, 2)
┌────────────────────────────────────────────────────┬────────────────────────────────────────────┐
│ lyrics                                             ┆ removes_pronouns                           │
│ ---                                                ┆ ---                                        │
│ str                                                ┆ str                                        │
╞════════════════════════════════════════════════════╪════════════════════════════════════════════╡
│ Everybody wants to rule the world                  ┆ Everybody wants to rule the world          │
│ Tell me what you want, what you really really want ┆ Tell  what  want, what  really really want │
│ Can you feel the love tonight                      ┆ Can  feel the love tonight                 │
└────────────────────────────────────────────────────┴────────────────────────────────────────────┘

传递带有模式和替换的映射也作为语法糖支持。

>>> _ = pl.Config.set_fmt_str_lengths(100)
>>> _ = pl.Config.set_tbl_width_chars(110)
>>> df = pl.DataFrame(
...     {
...         "lyrics": [
...             "Everybody wants to rule the world",
...             "Tell me what you want, what you really really want",
...             "Can you feel the love tonight",
...         ]
...     }
... )
>>> mapping = {"me": "you", "you": "me", "want": "need"}
>>> df.with_columns(
...     pl.col("lyrics").str.replace_many(mapping).alias("confusing")
... )
shape: (3, 2)
┌────────────────────────────────────────────────────┬───────────────────────────────────────────────────┐
│ lyrics                                             ┆ confusing                                         │
│ ---                                                ┆ ---                                               │
│ str                                                ┆ str                                               │
╞════════════════════════════════════════════════════╪═══════════════════════════════════════════════════╡
│ Everybody wants to rule the world                  ┆ Everybody needs to rule the world                 │
│ Tell me what you want, what you really really want ┆ Tell you what me need, what me really really need │
│ Can you feel the love tonight                      ┆ Can me feel the love tonight                      │
└────────────────────────────────────────────────────┴───────────────────────────────────────────────────┘