From: "Timothy C. May" <tcmay@got.net>
Date: Wed, 6 Nov 1996 10:49:51 -0800 (PST)
To: cypherpunks@toad.com
Subject: Sliderules, Logs, and Prodigies
In-Reply-To: <199611052244.OAA15345@toad.com>
Message-ID: <v03007806aea68cf963af@[207.167.93.63]>
MIME-Version: 1.0
Content-Type: text/plain




(Someone renamed my thread with the "[noise]" prefix. I have removed this
stupid prefix. Anything people think really is just noise should not even
be posted. I favor picking descriptive thread names, and try to do it
whenever I can, rather than cluttering up thread names with cutesy labels.)

At 2:44 PM -0800 11/5/96, Sean Roach wrote:

>If I remember my history right, the order that math was done often depended
>on the model of calculator it was done on.  I remember being warned as late
>as 1991 how some calculators may still still add before they multiply, and
>to use those parenthesis for good measure, just to be safe.

Well, it ain't _history_ only--it's also current. Some of us use RPN
(Reverse Polish Notation) calculators exclusively. (Even my screen
calculator I use on my Mac is an RPN one.)

The main split is between RPN and algebraic. Algebraic calculators use
parentheses to establish operator precedence and to alter precedence, RPN
calculators do not.

(Yes, purists will note, advanced RPN calculators have options for
parentheses, brackets, and other similar things, and can even process
algebraically. But not in the basic models, and the RPN computational
model, being stack-based, does not require them.)

To see how RPN works, visit any electronics store that carries
Hewlett-Packard calculators, especially the advanced ones like the H-P 48,
and read the first 5 pages of the instruction manual. It will all become
clear to you.



--Tim May


"The government announcement is disastrous," said Jim Bidzos,.."We warned IBM
that the National Security Agency would try to twist their technology."
[NYT, 1996-10-02]
We got computers, we're tapping phone lines, I know that that ain't allowed.
---------:---------:---------:---------:---------:---------:---------:----
Timothy C. May              | Crypto Anarchy: encryption, digital money,
tcmay@got.net  408-728-0152 | anonymous networks, digital pseudonyms, zero
W.A.S.T.E.: Corralitos, CA  | knowledge, reputations, information markets,
Higher Power: 2^1,257,787-1 | black markets, collapse of governments.
"National borders aren't even speed bumps on the information superhighway."