        RPN: a scientific calulator
        Written by J Landman

        Introduction:
            RPN was first concieved of about 4/89 when my old HP 15c died a
        painful death.  The LCD cracked after 3 years of trusty service.
        At that point I bought myself an HP-42s.  And I fell in love with
        it.  It handles complex numbers rather transparently.  It is very
        programmable.  It has many useful functions.  It is fun to play
        with.
            So I decided to attempt to emulate many of the functions of the
        42s in a computer program.  I needed a function library, and I
        needed a set of routines to deal with complex numbers.  I wrote
        both sets.  After all the smoke cleared, there was debugging yet to
        be done.  I did my best at debugging.  I know of one little one
        that slipped through.  That is the sign of the real part of inverse
        tangent of numbers > 1.  I will correct this as soon as possible.
            Otherwise, the program appears to work well.  My intention is to
        target it for students of physics and related fields.  I also
        intend to add improvements to it that would make it an acceptable
        data analysis tool.  I will include (in later versions as my
        schedule allows) vectors and matricies, more
        constants and units, and true programmability.  I have been
        experimenting with a program to take RPN input, and translate
        into 8088/8087 assembler code, so as make very tight, fast object
        code.  These bits of code would be callable as subroutines from
        most Microsoft languages.
            At the moment the program has many "scientific" functions.
        Hence I will call it a scientific calculator.
            Before I continue I must state that I developed this wholly on
        my own time, using my own equipment.  I spent several months worth
        of spare time tracking bugs, fixing mistakes, etc.  I have worked
        rather hard on this.
            I ask that you distribute this freely and actively, especially
        to BBS's in university communities.  Since I have invested so much
        of my time and effort to create and improve
        this (15 Months), and since I am a poor graduate physics
        student, I would appreciate any and all donations of funds to
        enable me to continue my development work.

            As well as the program, I have a rather complete library of
        subroutines and functions that work rather well with complex numbers.
        I will eventually include these as well, in object code form.  All of these
        subroutines and functions are callable from Microsoft Quickbasic
        v 4.5.  For that matter the program was also written in Quickbasic.
        The reason for this choice is simple.  Quickbasic is the easiest and
        fastest possible development enviornment I have found.  I may port
        the program to fortran in the future.  Pascal was not really a choice
        available to me at the time of the writing.
           I must say that I hope your experience is pleasent
        with my program.  The material is to be considered SHAREWARE.  It is
        copyrighted.  It may be distributed freely.  If you find it useful, then
        please do contribute to my efforts.
           Finally, about warranties, garuntees, etc.
        There are no warranties or garuntees associated with the
        use or misuse of this program.  There are no express or implied
        warranties or
        garuntees about the fitness of this program or any parts thereof, for
        any purpose whatsoever.  The program is used entirely at your own risk.
        SJ Scientific (any of its agents, employees, owners, etc..)
        is NOT LIABLE
        for any damage caused by the use or misuse of this program.  SJ
        Scientific assumes no responsibility nor Liability for the use
        or misuse of the results generated by this program.
        By executing the program or any portions thereof, you do agree to these
        terms.

        This means BE careful... If you screw up it aint my fault.  If
        the program screws up it aint my fault.  If your computer suddenly
        explodes into a zillion tiny little pieces after RPN does
        its complex mental gymnastics, then that as well aint my fault.
        If You lose all your valuable information because YOU didnt keep
        backup copies, it aint my fault, even if my program is the culprit.
        You are responsible for ANYTHING AND EVERYTHING ON YOUR OWN MACHINE.

        even simpler: dont blame me for your problems, I am not responsible
        , though I am usually happy to help resolve them, provided I
        have sufficient time.

        The purpose of the preceding paragraph is to protect my butt from
        those greedy lovers of litigation.  I use this program to generate
        numbers for my homework assignments.  It seems to generate the correct
        numbers.  So I trust it.  (I did compare EVERY function I have
        implemented
        against the tables in Abramowitz and Stegun, "Handbook of Mathematical
        Functions and Tables".  My advice to anyone designing and building
        some object that has a critical function in human well being is that
        you check and recheck your calculations.  Don't just rely upon a
        computer, as it will only report what you ask of it.  Hand calculation
        is slower, but you will catch mistakes made during computer use.

           Any and ALL suggestions for functions will be carefully considered.
        If I decide to use what you suggest, I will cite you as the source
        of the material in the manual.

        correspondence address:
                Joseph I Landman
                Physics and Astronomy Bldg,
			  666 Hancock Avenue,
                Wayne State University,
                Detriot, MI 48202

        EduNET:  LANDMAN@MSUPA.Pa.MSU.edu
        BITNET:  07480JLN at MSU
            or   LANDMAN@MSUPA.BITNET

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