Python_collections_OrderedDict有序字典部分功能介紹

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OrderedDict():實現字典的固定排序,是字典的子類

import collectionsdic = collections.OrderedDict()dic[‘k1‘] = 3dic[‘k2‘] = ‘nihao‘dic[‘k3‘] = 7print(dic)

結果：OrderedDict([(‘k1‘, 3), (‘k2‘, ‘nihao‘), (‘k3‘, 7)])

x.move_to_end():把一個元素移動到最後

import collectionsdic = collections.OrderedDict()dic[‘k1‘] = 3dic[‘k2‘] = ‘nihao‘dic[‘k3‘] = 7print(dic)dic.move_to_end(‘k2‘)print(dic)

結果：OrderedDict([(‘k1‘, 3), (‘k2‘, ‘nihao‘), (‘k3‘, 7)])OrderedDict([(‘k1‘, 3), (‘k3‘, 7), (‘k2‘, ‘nihao‘)])

x.popitem():移除最後一個寫入字典的值，並可返回擷取

x.pop():移除指定值並可返回擷取

 

Python_collections_OrderedDict有序字典部分功能介紹