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From: hogan@AEROSPACE.ARPA
Newsgroups: net.lang.ada
Subject: Physics Package
Message-ID: <8608111632.AA13161@aerospace.arpa>
Date: Mon, 11-Aug-86 12:31:36 EDT
Article-I.D.: aerospac.8608111632.AA13161
Posted: Mon Aug 11 12:31:36 1986
Date-Received: Tue, 12-Aug-86 15:27:29 EDT
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Organization: The ARPA Internet
List-Id: <comp.lang.ada>

If one uses Ada to strongly type each kind of physical unit (e.g. velocity,
acceleration, force, energy, etc.), then one either has to do many 
conversions to accomplish the necessary equations or provide a package
with many overloadings of common operators (e.g. *, +, -, /, etc).  Would
a phyics package with all of these types and overloaded operators be of
any use in the general community?  Has this been done before ?  Does anyone
know (does anyone care) ?  How has this problem been attacked in existing systems.  

I have a feeling that using separate Ada types for each different physical unit
when the different units must be frequently combined into equations to be
of any use, is somehow not in the spirit of good object oriented design with
Ada.  Does anyone have a different opinion ?

I will summarize replies that I receive.

Mike Hogan
hogan @ aerospace