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From: akcs.mitchell@hpcvbbs.UUCP (Mitchell Dickerman)
Newsgroups: comp.sys.handhelds
Subject: Relation plotter wanted
Keywords: relation plotter
Message-ID: <276432b1:1406comp.sys.handhelds@hpcvbbs.UUCP>
Date: 11 Dec 90 01:40:04 GMT
Lines: 10

Long ago, I had a wonderful program that plotted relations, i.e.
if you gave it X^2+Y^2-1, it drew the unit circle. I would love to
see a program like this for my 48, but I'm not much of a programmer.
In order to plot f(x,y)=0, one would have to begin with the pixel
in the upper left hand corner, and check the 3 adjacent pixels and
compare the sign of f(x,y) evaluated at those points. If a sign change
occured, it indicates a solution of f(x,y)=0, and that pixel should
be turned on. Am I making sense? Can someone give me a hand implementing
this?

Mitch