|Re: Why are 42S's so desirable ?|
Message #3 Posted by John Smith on 4 Feb 2003, 9:14 a.m.,
in response to message #1 by Bob
- size: HP42S is smaller and lighter than HP48/49, much more
convenient to carry around, easier to hold in your hand
- feature set: HP42S has most of the functions a technical user would ever need. Symbolic math and other allegedly esoteric features are of little everyday use.
- compatibility: the fact that HP42S' function set is a
superset of HP41C's is extremely important. You can key in almost all the many thousands of programs for the 41C series with little or no conversion whatsoever required. That you can't do with an HP48/49, unless using special software/hardware
- ease of use: many people prefer classical 4-level RPN stack plus Last X than RPL's indefinite stack and strict
adherence to postfix notation. You can do virtually any calculation using the 4-level stack, and it's easy to visualize. You also get automatic top level replication, which is very convenient. You always have LastX available,
and you can't get an error trying to execute some function
with insufficient arguments in the stack, as the stack
is always 4-level deep and can't really be 'empty'.
On the other hand, it's very easy to get lost while trying
to keep in mind a variable number of arguments in a large number of stack registers, you can't be 100% sure that LastArg is enabled
(and frequently it isn't, to save memory), you don't get
top level replication, and you can get unexpected errors
if the stack gets empty.
- language: RPL is perhaps far too complicated for casual
users, with its strict adherence to postfix notation, and
thus it's more difficult to write casual programs on it,
debug them, and understand them a few months later. It was
already somewhat difficult with classical RPN, but RPL
increases the difficulty by an order of magnitude.
- quality: HP42S operating system is a thoroughly debugged
product, with few bugs and no important ones. HP48/49's
is buggier, and has required a number of iterations to
bring it to an acceptably stable state. It's been the case
that you couldn't really trust the answers it gave, while
I have yet to see some worst-case example of a wrong result given by an HP42S.
- documentation: HP42S shipped with two large, thick,
quality spiral manuals, of very high, classical HP quality.
Not so with the HP48/49.
There are many more reasons, but these few will give an idea.