Re:Graphtoy
by TeMPOraL on Monday January 04, 2021 @08:14AM
(#25630875)
Yup, I usually used EvalDraw in (x,y) mode to graph inequalities. You have to remember though that equations like x=y or x-y = 0 represent a line - an infinitely thin object - so EvalDraw will likely not draw you anything given such input. You have to translate your equation into something that has thickness. E.g. an f(x) = 0 into abs(f(x)) < 0.01
For instance, GP's example:
(x,y)
abs(sin((1+sin(x+y))asin(.5(sin(x)+sin(y)))+(1+sin(x-y))asin(.5(cos(x)+cos(y)))))<0.01
Draws a beautiful red chain-link fence on blue background.
If you can rewrite your formula to give you a value between 0 and 1, you'll get a nice color gradient. And then you can have more direct control over colors using some of the things I described in the linked comment.
For instance, GP's example: (x,y) abs(sin((1+sin(x+y))asin(.5(sin(x)+sin(y)))+(1+sin(x-y))asin(.5(cos(x)+cos(y)))))<0.01
Draws a beautiful red chain-link fence on blue background.
If you can rewrite your formula to give you a value between 0 and 1, you'll get a nice color gradient. And then you can have more direct control over colors using some of the things I described in the linked comment.