NetNews Usenet Archive 1992 #26/NN_1992_26.iso/spool/comp/arch/10523

Internet Message Format | 1992-11-08 | 1.6 KB

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From: [e-mail] (Chris Torek)
Newsgroups: comp.arch
Subject: integer/BCD/... dollars (was IEEE used for Dollars and Cents)
Date: 8 Nov 1992 08:16:44 GMT
Organization: Lawrence Berkeley Laboratory, Berkeley
Lines: 22
Message-ID: <[e-mail]>
References: <[e-mail]>
Reply-To: [e-mail] (Chris Torek)
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In article <[e-mail]> [e-mail] (Don Stokes) writes:
>... most machines only handle 32 bit or less integers cleanly, and
>with two decimal places that's only up to $21,474,836.47 (assuming signed
>integers).

Signed integers are not an absolute must, but precision greater than
one penny is; most businesses seem to keep records to five digits or so.

>Machines that can handle 64 bit integers cleanly will make this problem
>largely go away.  8-)

Hm, my kitchen arithmetic says that 2^64 only represents 1844 trillion
dollars in mills.  At its current growth rate, the U.S. national debt
will exceed this well within the next century.  Of course, by then the
nation itself will be completely bankrupt, so this will not matter. :-)

Current 32-bit microprocessors are capable of handling 64-bit quantities
moderately well.  Current versions of GCC support them directly.  64-bit
integer arithmetic is well on its way to becoming established practise.
--
In-Real-Life: Chris Torek, Lawrence Berkeley Lab CSE/EE ([phone])
Berkeley, CA        Domain:    [e-mail]