T

#### Tom Anderson

I would quite like to represent some numbers in fixed point, and do

arithmetic with them.

These numbers will mostly not be more than a bilion, and will probably

never be more than a hundred billion. Some of them, i will need to

represent to eight decimal places. I'd like to be able to multiply two

large numbers, but i suspect will not need to multiply three. 11 * 2 + 8 =

30 decimal digits; that's about 100 bits, so 128 bits would be big enough

(about 5 decimal digits of headroom).

Can anyone suggest an existing library for doing fixed-point arithmetic

which would cover this?

I have googled, but not found anything. There are a few fixed-precision

libraries aimed at J2ME (i assume because old phones didn't have

floating-point units?). There's something called jExigo, but it's 64-bit

and the code doesn't look great.

It's quite possible that there is no such library. But i thought it

prudent to ask before writing one myself.

Thanks,

tom