Quote from: Enochian on June 09, 2011, 08:38:07 AM

Quote from: bitcoinhelper on June 09, 2011, 06:38:27 AM

Please, just use integer (i.e. fixed point) arithmetic for financial data and stop writing shoddy code. It's a no brainer, really...

Floating point arithmetic which can represent the integer values exactly isn't going to give a different answer than fixed point arithmetic. Look at all the actuarial programs written in APL, whose numeric prototype is a double precision float or complex.

The alleged horrors of float for financial math are mostly FUD. Lots of COBOL programs use a comp-3 floating type because it is faster than character or packed decimal arithmetic.

Statements like this make me wonder if you have ever written portable floating point code.

You might be ok if the system you run on implements IEEE-754 rules. However, this day & age the Bitcoin client is being run on more & more small devices, some of which might not even have an FPU. Not only that, but those which do are very likely not to follow 754 rules in particular, making their output theoretically differ from the result on a 754-based machine. Those bugs are so much fun to find. Tongue

The bottom line is that quality programming starts with good discipline, and financial software should always use fixed point representations. Some companies will literally fire you if they see floating point in your code, and it's not because they are stupid.