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HomeBackend DevelopmentPython Tutorial从零学Python之入门(二)基本数据类型

简单的数据类型以及赋值

变量不需要声明

Python的变量不需要声明,你可以直接输入:

代码如下:


>>>a = 10

那么你的内存里就有了一个变量a, 它的值是10,它的类型是integer (整数)。 在此之前你不需要做什么特别的声明,而数据类型是Python自动决定的。

代码如下:


>>>print a
>>>print type(a)

那么会有如下输出

代码如下:


10

这里,我们学到一个内置函数type(), 用以查询变量的类型。

回收变量名

如果你想让a存储不同的数据,你不需要删除原有变量就可以直接赋值。

代码如下:


>>>a = 1.3
>>>print a,type(a)

会有如下输出

代码如下:


1.3

我们看到print的另一个用法,也就是print后跟多个输出,以逗号分隔。

基本数据类型

代码如下:


a=10         # int 整数
a=1.3        # float 浮点数
a=True       # 真值 (True/False)
a='Hello!'   # 字符串

以上是最常用的数据类型,对于字符串来说,也可以用双引号。

(此外还有分数,字符,复数等其他数据类型,有兴趣的可以学习一下)

总结

变量不需要声明,不需要删除,可以直接回收适用。

type(): 查询数据类型

整数,浮点数,真值,字符串

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