Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!hp-pcd!hpcvlx!paulm
From: paulm@hpcvlx.cv.hp.com (Paul J. McClellan)
Newsgroups: comp.sys.handhelds
Subject: Re: HP48 units bug
Message-ID: <110540017@hpcvlx.cv.hp.com>
Date: 19 Sep 90 20:26:38 GMT
References: <1990Sep19.024034.15518@mintaka.lcs.mit.edu>
Organization: Hewlett-Packard Co., Corvallis, OR, USA
Lines: 29

> I have discovered what appears to be a previously unreported bug in my 
> revision D ROMs.  The units application fails to properly handle units
> with fractional powers.  The problem is easy to demonstrate by taking the
> square root of 1_N (that's one Newton) and then trying to convert to base
> units with UBASE.  The correct answer is, of course, 1_kg^.5*m^.5/s but the
> calculator returns 1_kg*m/s.  The calculator does not handle fractional powers
> of units, rather it simple rounds to the nearest integer power.  Another 
> interesting result is that the UBASE of 1_N^.3333333 returns 1_1/s.  It appears
> that UFACT calls UBASE because it suffers from the same bug. 

...

> Christopher B. Moore
> cmoore@space.mit.edu

Please explain to us what physical quantity is represented by the square
root of a Newton.  The unit application was designed to solve useful
problems in a reasonable amount of time and memory space, and fractional
unit exponent support was intentionally omitted to achieve this.

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