如何将二进制数转换为整数而不使其为正数

i need a function that will convert binary with sign to integer.

我需要一个函数，将二进制符号转换为整数。

int("1010",2) 
#this will be converted to 10 instead of -6 - 
# i want a fucnction that will convert it into -6 

3 个解决方案

#1

You may use the bitstring module:

您可以使用bitstring模块：

from bitstring import Bits
nr = Bits(bin='1010')
print(nr.int) # .int here acts as signed integer. If you use .uint it will print 10

#2

There's no built-in way to do this, but it's easy enough to adjust the positive value by checking the first bit of your string.

没有内置的方法可以做到这一点，但通过检查字符串的第一位就可以轻松调整正值。

def signed_bin(s):
    n = int(s, 2)
    if s[0] == '1':
        n -= 1<<len(s)
    return n

# test

w = 4
for i in range(1<<w):
    s = '{:0{}b}'.format(i, w)
    print(i, s, signed_bin(s))

output

产量

 0 0000 0
1 0001 1
2 0010 2
3 0011 3
4 0100 4
5 0101 5
6 0110 6
7 0111 7
8 1000 -8
9 1001 -7
10 1010 -6
11 1011 -5
12 1100 -4
13 1101 -3
14 1110 -2
15 1111 -1

#3

According to answer of john, You may also use BitArray to do this task :

根据约翰的回答，你也可以使用BitArray来完成这个任务：

>>> from bitstring import BitArray
>>> b = BitArray(bin='1010')
>>> b.int
-6