From: Gavin Sinclair <gsinclair@...>
Date: 2002-12-11T07:37:44+09:00
Subject: Re: Proper Type for Dollar Amount

From: "William Djaja Tjokroaminata" <billtj@y.glue.umd.edu>


> Jim Weirich <jweirich@one.net> wrote:
> > This is a consequence of representing numbers in floating point and is
> > common whenever dealing with floating point numbers.  Last week at work,
> > I came across a situation where a sum of monetary amounts were off by a
> > penny ... Yes, they were using floating point to represent dollar
> > amounts.  Never a good idea.
>
> Well, you can search comp.lang.c about a thread on what type to use
> (int/long/double/etc.) to represent dollar amounts (including the
> cents).  I don't think there is a clear answer that representing dollar
> amounts with floating point is a bad idea.  It depends on what kinds of
> operations you are going to do, which in this case is a division.
>

In the rare case that I have represented money, I've used an integer to
represent the nuber of cents, with a "Currency" (or similar) class wrapped
around it providing lots of groovy methods.

Gavin