python 只number类型补充(将字符串型的二进制数转换为int类型)

我们都知道将int型转换为字符串是:

string = str(123456)

我们还知道将一个十进制数转换为二进制数:

num = bin(123)

我们还知道将一个二进制转换为十进制数:

int_num = int(0b11111)

如何将一个字符串类型的十进制数转换为二进制数呢,很简单

先将字符串类型转换为int型,然后在转为二进制数不就好了吗?

string = "123"
int_num = int(string)
bin_num = bin(int_num)

好了,大功告成!很简单!

那么,如何将一个字符串类型的二进制数(类似于这样的 "1111111")转换为十进制数呢?

有人肯定是这么想的:

bin_str = "1111"
bin_num = bin(bin_str)
int_num = int(bin_num)

但是会发现报错:

Traceback (most recent call last):
  File "G:/python作业/test-1/si1.py", line 313, in <module>
    bin_num = bin(bin_str)
TypeError: 'str' object cannot be interpreted as an integer

然而python中的int方法就可以办到,完成转换:

bin_str = "1111"

int_num = int(bin_str, 2)
print(int_num)

执行结果:

C:\Python36\python.exe G:/python作业/test-1/si1.py
15

Process finished with exit code 0

 

int(x=0) -> integer
        int(x, base=10) -> integer
        
        Convert a number or string to an integer, 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 the
        given base.  The literal can be preceded by '+' or '-' and be surrounded
        by whitespace.  The base defaults to 10.  Valid bases are 0 and 2-36.
        Base 0 means to interpret the base from the string as an integer literal.
        >>> int('0b100', base=0)
        4
        # (copied from class doc)

翻译:

待续............