Re: Hp49G and RPN syntax


scottblakely@xxxxxxxxx ha escrito:

> @ Clapton.
>
> My confusion stemmed from the assumption that you were using a 49G and
> I thought perhaps there was a difference in configuration or something.
>
> Thanks for all of your help.

Scott:
I actually own a 49 g+ but i have a 48 sx since 1992 when I was an
engineering student.
As a matter of fact the procedure for managing with units that Joseph
Horn (God bless him for those marvelous Goodies Disks for hp 48) and I
told you came from the times of the hp 48 (even hp 28) and you can't
find it in the hp 49 G or 49 g+ menu; surely you have found something
about the Convert command inside the tools menu of units. That's
correct but it's faster the way that the big JKH and I suggested you.
It's a little trick from old warriors.
So, if you really want to use your calculator in RPN mode, the
suggestion of Arnaud is the better way, learn reading the 48 manual,
since the 48 only had RPN mode (and that's the reason why I love hp
calculators).

I've always thought the real power of RPN come from programming, if you
make a program for this wonderful machine you will find that you can
use every command you have defined directly, so User RPL (the first
programming languagefor hp calculators) is very compact, powerful and
the programs are very short compared with tehe other ones (like basic,
very common in other calculators like TI).
An User RPL program with only 1 or 2 kB can do wonderfulk things, like
solving a system of non-linear equations or anithing you can imagine.
Now the other hand. User RPL is not easy to use and the programs
written on it are really difficult to understand if they don't come
with notes. The natural way of programming User RPL is in RPN mode,
really you have a LIFO stack and you can manage it directly, so it's a
lower level language for programming than Basic, with many advantages.

User RPL is only the first step in programming hp calculators. Therae
are two other languages, of course more difficult and powerful; in
order System RPL (or SYS RPL) and machine language (or ML).
All the greatest classics for hp 48 and 49 aplications were made using
one or both, like FEM49, XCELL, SOLVESYS, and many, many others.
And so, we find the real strenght of this calculator, the reason why,
for me (and for many others) it has no equal: the applications
developped through years and years. This is a real, professional
machine and you can find almost everything you need ( visit
www.hpcalc.org and take a look). If you need an application for
structures, you have FEM 49, if you need a spreed ***, yoyu have
XCELL, if you need a program that solves everything you have SOVELSYS,
if you need Simplex algorithm, you can find dozens, if you need
hydraulics aplications, the same, if you need economics, ....if you
need games, of course.
And of course the emulator for the pc is wonderful; you can fid
applications like hpuseredit that allos you to make your own code in
your PC in a very frienshp enviroment.
Everything you need is still programmed, but you can try to find some
new problem and make your own code. It's a real surprise when you
finish a programm that solves a complex question an it has only 1 kB
(try it).

Finally, if you loose your prevention to RPN you will discover another
world in calculators. Of course, that's only my opinion, but after 13
years of an everyday use I think I have a founded opinion.

Cheers

.