38 lines
1.2 KiB
Markdown
38 lines
1.2 KiB
Markdown
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# Python 字典的基本用法
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> 原文：<https://www.pythonforbeginners.com/dictionary/python-dictionary-basic-usage>
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Dictionary 是 Python 中的另一种数据类型。
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## 字典概述
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```py
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A dictionary maps a set of key to a set of values.
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Dictionaries in Python are also known as hash tables.
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It requires that the keys are unique (within one dictionary), while the values maynot.
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The values of a dictionary can be of any type, but the keys must be of an
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immutable data type such as strings, numbers, or tuples.
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Dictionaries are like lists mutable
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A dictionary is created with a pair of braces {}.
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For example, dic = {} creates an empty dictionary.
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Each key is separated from its value by a colon (:)
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Placing a comma-separated list of key:value pairs within the braces adds initial
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key:value pairs to the dictionary; this is also the way dictionaries are written
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on output.
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The main operations on a dictionary are storing a value with some key and
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extracting the value given the key.
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If you store using a key that is already in use, the old value associated with
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that key is forgotten.
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```
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别忘了查看[字典备忘单](https://www.pythonforbeginners.com/dictionary/ "dictionary")
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