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From: glen herrmannsfeldt <gah@ugcs.caltech.edu>
Newsgroups: comp.lang.java.programmer
Subject: Re: Fixed-point arithmetic library
Date: Mon, 27 Feb 2012 00:59:00 +0000 (UTC)
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Robert Klemme <shortcutter@googlemail.com> wrote:

(snip)
>> I would quite like to represent some numbers in fixed point, 
>> and do arithmetic with them.

> Fixed point math is susceptible to precision issues which can 
> be more severe than those of float and double: 0.01 * 0.2 -> 0.00

In PL/I, if you multiply, you get the appropriate number if digits
after the radix point.

FIXED DECIMAL(3,2) times FIXED DECIMAL(2,1) generates a 
product of FIXED DECIMAL(5,3). If you force it to throw away
low order digits, then, yes you can lose precision.

-- glen