Question

我知道*为0或更多，+为1或更多，但如果我想表示2个或更多（超过1）怎么办？

例如，我有

>>> y = 'U0_0, P33, AVG'
>>> re.findall(r'[a-zA-Z]+', y)
['U', 'P', 'AVG']

但我只想获得有2个或更多字母的那些。在此示例中，AVG。

我该怎么做？

Answer 1

您可以使用以下代替*或+：

{2,}     (two or more)

此外，如果你想匹配2到5，你可以这样做：

{2,5}    (two to five example)

Answer 2

y = 'U0_0, P33, AVG'
print re.findall(r'[a-zA-Z]{2,}', y)

                            ^^^

{m,n} Causes the resulting RE to match from m to n repetitions of the preceding RE, attempting to match as many repetitions as possible. For example, a{3,5} will match from 3 to 5 'a' characters. Omitting m specifies a lower bound of zero, and omitting n specifies an infinite upper bound. As an example, a{4,}b will match aaaab or a thousand 'a' characters followed by a b, but not aaab. The comma may not be omitted or the modifier would be confused with the previously described form.

Python正则表达式：是否有一个符号来搜索模式的多个出现？

2 个答案: