[Python] Replicating C Fixed-Point Math in Python

I am attempting to replicate a DSP algorithm in Python that was originally written in C. The trick is I also need to retain the same behavior of the 32 bit fixed point variables from the C version, including any numerical errors that the limited precision would introduce.

The current options I think are available are:

I know the python Decimal type can be used for fixed-point arithmetic, however from what I can tell there is no way to adjust the size of a Decimal variable. To my knowledge numpy does not support doing fixed point operations.

I did a quick experiment to see how fiddling with the Decimal precision affected things:

>>> a = dc.Decimal(1.1)
>>> a
Decimal('1.100000000000000088817841970012523233890533447265625')
>>> sys.getsizeof(a)
104
>>> dc.getcontext().prec = 16
>>> a = dc.Decimal(1.1)
>>> a
Decimal('1.1999999999999999555910790149937383830547332763671875')
>>> sys.getsizeof(a)
104


There is a change before/after the precision change, however there are still a large number of decimal places. The variable is still the same size, and has quite a few decimal places after it.

How can I best go about achieving the original objective? I do know that Python ctypes has the C language float, but I do not know if that will be useful in this case. I do not know if there is even a way to accurately mimic C type fixed point math in Python.

Thanks!

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