Question

我正在使用Python集合库打印出字符串中最常见的字符以及重复的次数。

import collections
results = collections.Counter("this is fun")
listresults= results.most_common()
print listresults

这就是我的结果：

[(' ', 2), ('i', 2), ('s', 2), ('f', 1), ('h', 1), ('n', 1), ('u', 1), ('t', 1)]

这不是我想要的。我想要像

这样的东西

[(2,"i") (2, " "),...]

有谁知道如何产生预期的结果？

Answer 1

你可以试试这个：

>>> from collections import Counter
>>> results = Counter("this is fun")
>>> r = results.most_common()
>>> what_i_want = [(y, x) for x, y in r]
>>> what_i_want
[(2, ' '), (2, 'i'), (2, 's'), (1, 'f'), (1, 'h'), (1, 'n'), (1, 'u'), (1, 't')]

我使用list comprehension因为列表推导通常比使用for子句更有效，占用的空间更少。不过，根据下面的评论，for条款看起来像是jamylak所建议的：

>>> what_i_want = []
>>> for x, y in r:
    what_i_want.append((y, x))
>>> what_i_want
[(2, ' '), (2, 'i'), (2, 's'), (1, 'f'), (1, 'h'), (1, 'n'), (1, 'u'), (1, 't')]

Answer 2

另一种稍微不那么可读但仍然相当pythonic的方式：

import collections
results = collections.Counter("this is fun")
listresults= results.most_common()
print listresults
print zip(*reversed(zip(*listresults)))

使用Python修改collections.Counter的输出

2 个答案: