July 2017
Intermediate to advanced
398 pages
11h 54m
Chinese
Content preview from Python数据处理
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22
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第
2
章
现在可以将这些动物的数量放在一个列表中：
animal_counts = [cats, dogs, horses]
在
Python
解释器中输入
animal_counts
，
Python
会返回下面的值：
[2, 5, 1]
变量为我们保存信息。当我们输入变量名时，
Python
返回的是变量中保存的值。
你还可以创建包含列表的列表。比如说，创建动物名字的列表：
cat_names = ['Walter', 'Ra']
dog_names = ['Joker', 'Simon', 'Ellie', 'Lishka', 'Fido']
horse_names = ['Mr. Ed']
animal_names = [cat_names, dog_names, horse_names]
在
Python
解释器中输入
animal_names
，
Python
会返回下面的值：
[['Walter', 'Ra'], ['Joker', 'Simon', 'Ellie', 'Lishka', 'Fido'], ['Mr. Ed']]
你不必输入所有的名字来创建包含列表的列表。原始变量（
cat_names, dog_names, horse_
names
）也是列表，它们仍然可用。例如，输入
cat_names
，你会得到
['Walter', 'Ra']
作
为返回值。
前面已经探索了列表，下面我们继续探索一个稍微复杂一点的数据容器，叫作字典。
2.2.3
字典
字典比变量或列表更加复杂。“字典”这个名字是很贴切的。将 ...
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