已排序是重复条目

Question

我想按嵌套 lsits 的第二个条目中的数值对嵌套列表进行排序。

name= ['Harry', 'Berry', 'Tina', 'Akriti', 'Harsh']
score = [37.21, 37.21, 37.2, 41.0, 39.0]

mylist = [[title, grade] for title in name for grade in score]
test = sorted(mylist, key=lambda x:x[1])

但出于某种原因，这会重复条目。为什么它不按嵌套列表中的第二个条目对列表进行排序？

 test
    [['Harry', 37.2], ['Berry', 37.2], ['Tina', 37.2], ['Akriti', 37.2], ['Harsh', 37.2], `['Harry', 37.21], ['Harry', 37.21], ['Berry', 37.21], ['Berry', 37.21], ['Tina', 37.21], ['Tina', 37.21], ['Akriti', 37.21], ['Akriti', 37.21], ['Harsh', 37.21], ['Harsh', 37.21], ['Harry', 39.0], ['Berry', 39.0], ['Tina', 39.0], ['Akriti', 39.0], ['Harsh', 39.0], ['Harry', 41.0], ['Berry', 41.0], ['Tina', 41.0], ['Akriti', 41.0], ['Harsh', 41.0]]`

Answer 1

你想要zip:

>>> name= ['Harry', 'Berry', 'Tina', 'Akriti', 'Harsh']
>>> score = [37.21, 37.21, 37.2, 41.0, 39.0]
>>> sorted(zip(score, name))
[(37.2, 'Tina'), (37.21, 'Berry'), (37.21, 'Harry'), (39.0, 'Harsh'), (41.0, 'Akriti')]

将 zip 视为将两个列表相加：

[(score[0], name[0]), (score[1], name[1]), ...]

而您所做的嵌套理解更像是将它们相乘：

[[name[0], score[0]], [name[1], score[0]], [name[2], score[0], ..., [name[0], score[1]], [name[1], score[1]], [name[2], score[1], ...]

Answer 2

你迭代了两次。

# using enumerate
mylist = [[title, score[ind]] for ind, title in eunmerate(name)]

# Using zip
mylist = zip(name, score)

已排序是重复条目

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