Python-列表

>>> L = ['spam', 'Spam', 'SPAM!']

>>> L[0:2] = ['eat', 'more']

>>> L

['eat', 'more', 'SPAM!']

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>>> L[1:2] = [4,5]

>>> L

['eat', 4, 5, 'SPAM!']

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>>> L.append('please')

>>> L

['eat', 4, 5, 'SPAM!', 'please']

>>> L.sort()

TypeError

因为'eat'是String，而4, 5是int

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使用append函数，执行起来要比"+"合并速度快，因为append函数不用生成新的对象。

L[len(L):] = [X] 与 L.append(X) 一样；

L[:0] = [X] 即在列表前端附加；

以上两者都会删除空分片，并插入X；

 

注意：append函数与sort函数，并没有返回值；

注意2：append函数每次只能增加一个元素

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pop函数为删除并返回一个元素，默认返回最后一个；

>>> L = ['spam', 'eggs', 'ham', 'toast']

>>> L.remove('eggs')

>>> L 

['spam', 'ham', 'toast']

>>> L.pop(1)

'ham'

>>> L

['spam', 'toast']

>>> del L[0]

>>> L

['toast']

>>> L = L + ['GOOD', 'TEST']

[’toast', 'GOOD', 'TEST']

>>> del L[1:]

['toast']

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 L[1:] = [] 与 del L[1:] 相同
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转载于:https://www.cnblogs.com/yy-is-ing/p/3940061.html