Python:计算字符串中列表项的出现次数

Question

如果我有以下列表

vowels = ["a","e","i","o","u"]

和另一个清单

words = ["happiness", "yellow"]

我如何计算每个单词中的元音数量,即幸福= 3,黄色= 2？

Answer 1

使用列表理解:

>>> vowels = ["a","e","i","o","u"]
>>> words = ["happiness", "yellow"]
>>> [sum(c in vowels for c in word) for word in words]
[3, 2]

如果要在单词和出现之间进行映射,请使用字典理解:

>>> {word: sum(c in vowels for c in word) for word in words}
{'happiness': 3, 'yellow': 2}

转换vowels为set将使其更有效.