Unsigned Fixed Point... With a little bit of work can work for signed, will convert to signed for large numbers if you try to convert to float or string... Not much interest in fixing, because it works for my little 16 bit numbers (and masks down to your

cw_fixed_point.py

class UFixedPoint(object):
    def __init__(self, num, m, n):
        self.mask = 2**(m + n) - 1
        self.k = (1 << (n - 1))
        self.m = m
        self.n = n
        
        temp = int(num * 2**self.n)
        self.value = temp & self.mask 

    def __add__(self, other):
        # Currently only allow same Qm.n Floats
        if (self.m == other.m) and (self.n == other.n):
            temp = UFixedPoint(0, self.m, self.n)
            temp.value = (self.value + other.value) & self.mask
            return temp
        else:
            return 0

    def __sub__(self, other):
        if (self.m == other.m) and (self.n == other.n):
            temp = UFixedPoint(0, self.m, self.n)
            temp.value = (self.value - other.value) & self.mask
            return temp
        else:
            return 0

    def __mul__(self, other):
        if (self.m == other.m) and (self.n == other.n):
            temp = UFixedPoint(0, self.m, self.n)
            temp.value = (self.value * other.value) + self.k
            temp.value >>= self.n
            return temp
        else:
            return 0

    def __div__(self,other):
        if (self.m == other.m) and (self.n == other.n):
            temp = UFixedPoint(0, self.m, self.n)
            temp.value = self.value << self.n
            temp.value += (other.value >> 1)
            temp.value = temp.value/other.value
            return temp
        else:
            return 0

    def __float__(self):
        return (float(self.value) / (2**self.n))

    def __str__(self):
        return "%f" % float(self)

num = 1.5
num = UFixedPoint(num, 12, 4)
numb = UFixedPoint(440, 12, 4)
print numb