75 lines
1.6 KiB
Markdown
75 lines
1.6 KiB
Markdown
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# Python 中的变量
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> 原文：<https://www.pythonforbeginners.com/basics/python-variables>
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## 变量
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您可以使用任何字母、特殊字符“_”和提供的每个数字
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而不是以它开头。
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在 Python 中有特殊含义的空格和符号，如“+”和“-”是不允许的
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。
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我通常使用小写字母，单词之间用下划线隔开，以提高可读性。
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记住变量名是区分大小写的。
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Python 是动态类型的，这意味着你不必声明每个变量是什么类型。
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在 Python 中，变量是文本和数字的存储占位符。
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它必须有一个名称，以便您能够再次找到它。
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变量总是被赋予等号，后跟
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变量的值。
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Python 有一些保留字，不能用作变量名。
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这些变量在程序中被引用来得到它的值。
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变量的值可以在以后更改。
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**将值 10 存储在名为 foo** 的变量中
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```py
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foo = 10
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```
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**将 foo+10 的值存储在名为 bar** 的变量中
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```py
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bar = foo + 10
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```
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## 一些不同变量类型的列表
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```py
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x = 123 # integer
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x = 123L # long integer
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x = 3.14 # double float
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x = "hello" # string
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x = [0,1,2] # list
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x = (0,1,2) # tuple
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x = open(‘hello.py’, ‘r’) # file
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You can also assign a single value to several variables simultaneously multiple
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assignments.
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Variable a,b and c are assigned to the same memory location,with the value of 1
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a = b = c = 1
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```
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#### 例子
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```py
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length = 1.10
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width = 2.20
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area = length * width
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print "The area is: " , area
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This will print out: The area is: 2.42
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```
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##### 更多阅读
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[http://python.org/](https://python.org/ "python")
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