** Addendum July 1, 1997 **

  Archiving this program for distribution has caused me to run this
program for the first time since 1993, so here are some notes
regarding Planets.


== DATA FILES ==

  Note that this program will automatically create some data files.
The main file, PLANETS.DAT contains information regarding the data
banks, and a PLANETx.DAT (x = # of data bank) will be created for
each set of data you create. If you wish to recalculate the data
without reentering the initial data, you can simply edit the data
file for the bank and remove all data past the original x lines of
data (the first line, 2nd character will be an integer value of
the number of planets, and then the next 'x' lines following should
be kept. All lines after that can be removed)


== DATA ENTRY ==

  As mentioned in the documentation, the numbers are 32-bit floating
point values. This means that as an integer, the valid range is
-2,147,483,648 to +2,147,483,647, however the numbers will quickly
become floating point, so I would recommend staying within a range
of -1,000,000 to +1,000,000 TOPS. In reality, however, the program
will work fine using much smaller values (-128 to +128, for example.)


== SPEED OF PROGRAM ==

  This program was originally developed on an 8MHz 80286. Nowadays 
I own a 200MHz 80686 (Pentium Pro). Times have changed, and the 
450+ MIPS PPro crunches numbers a LITTLE faster than the 0.9 MIPS
80286 did. Thus, I recommend either using an older machine or using
one of the slowdown programs available (mo'slo or slowdown).

  One semi-cheesy way of slowing the program down without doing it
through software is to copy the program onto a floppy disk and 
running it from there. Since Planets will be writing the data it
calculates to a data file, the speed of the disk drive will limit
the speed of the program. If you can disable a disk cache, that
would slow it down even more.

  By the way, it was developed using Microsoft Quick C 2.5 for DOS,
and for a more interesting note, the 286 that it was developed on
was an A2286 Bridgeboard in an Amiga 2500/30 with a Boca SuperX VGA
card. You thought the Macintosh was the first hybrid computer. HA!


== PLANET DISPLAY ==

  When a planet zips off the screen out into empty space, the display
will 'zoom out' to show all of the planets on the same screen. You
can tell when it does this as the planets will appear to slow down,
and the planets which zoomed off will reappear. Unfortunately, I never
wrote into the program a means of re-scaling the planet diameters,
nor did I create a 'aspect ratio' display. Just pointing this out...


== CONCLUSION ==

  This program was for a Physics 101 project at Miami University of
Ohio. Other people wrote papers, some did research, I wrote a program.
This was never meant to be 'professional', I meant it more for the
results than the appearance.

  If you have any questions, comments, flames, etc.. please don't 
hesitate to email me at bernstbj@ix.netcom.com .. have fun!
