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  • Python内置函数(9)——int

    英文文档:

    class int(x=0class int(xbase=10)

    Return an integer object constructed from a number or string x, or return 0 if no arguments are given. If x is a number, return x.__int__(). For floating point numbers, this truncates towards zero.

    If x is not a number or if base is given, then x must be a string, bytes, or bytearray instance representing an integer literal in radix base. Optionally, the literal can be preceded by + or - (with no space in between) and surrounded by whitespace. A base-n literal consists of the digits 0 to n-1, with a to z (or A to Z) having values 10 to 35. The default base is 10. The allowed values are 0 and 2-36. Base-2, -8, and -16 literals can be optionally prefixed with 0b/0B0o/0O, or 0x/0X, as with integer literals in code. Base 0 means to interpret exactly as a code literal, so that the actual base is 2, 8, 10, or 16, and so that int('010', 0) is not legal, while int('010') is, as well as int('010', 8).

    说明:

      1. 不传入参数时,得到结果0。

    >>> int()
    0

      2. 传入数值时,调用其__int__()方法,浮点数将向下取整。

    >>> int(3)
    3
    >>> int(3.6)
    3

      3. 传入字符串时,默认以10进制进行转换。

    复制代码
    >>> int('36')
    36
    
    >>> int('3.6')
    Traceback (most recent call last):
      File "<pyshell#2>", line 1, in <module>
        int('3.6')
    ValueError: invalid literal for int() with base 10: '3.6'
    复制代码

      4. 字符串中允许包含"+"、"-"号,但是加减号与数值间不能有空格,数值后、符号前可出现空格。

    复制代码
    >>> int('+36')
    36
    >>> int('-36')
    -36
    >>> int('   -36        ')
    -36
    >>> int(' - 36        ')
    Traceback (most recent call last):
      File "<pyshell#7>", line 1, in <module>
        int(' - 36        ')
    ValueError: invalid literal for int() with base 10: ' - 36   
    复制代码

      5. 传入字符串,并指定了进制,则按对应进制将字符串转换成10进制整数。

    复制代码
    >>> int('01',2)
    1
    >>> int('02',3)
    2
    >>> int('07',8)
    7
    >>> int('0f',16)
    15
    复制代码
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  • 原文地址:https://www.cnblogs.com/lincappu/p/8144664.html
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