How to get the signed integer value of a long in python?

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If lv stores a long value, and the machine is 32 bits, the following code: 

iv = int(lv & 0xffffffff)

results an iv of type long, instead of the machine's int.

How can I get the (signed) int value in this case?

signed unsigned python
8 Answers

If you know how many bits are in the original value, e.g. byte or multibyte values from an I2C sensor, then you can do the standard Two's Complement conversion:

def TwosComp8(n):
    return n - 0x100 if n & 0x80 else n

def TwosComp16(n):
    return n - 0x10000 if n & 0x8000 else n

def TwosComp32(n):
    return n - 0x100000000 if n & 0x80000000 else n
user_33448530

In case the hexadecimal representation of the number is of 4 bytes, this would solve the problem.

def B2T_32(x):
  num=int(x,16)
  if(num & 0x80000000): # If it has the negative sign bit. (MSB=1)
    num -= 0x80000000*2
  return num
print(B2T_32(input("enter a input as a hex value\n")))
user_176751160
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