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Show HN: A Sierpinski Valentine in 4 equations

72 points| harmonium1729 | 11 years ago |desmos.com | reply

10 comments

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[+] darklajid|11 years ago|reply
Unsupported browser.

Desmos works best on your version of Android if you use the Chrome Browser.

(Close page in Aurora, no clue what "Desmos" is but I don't care by now)

[+] splike|11 years ago|reply
How the heck do people come up with these equations? Is it purely mathematical knowledge, knowing what functions look like when plotted?
[+] electronvolt|11 years ago|reply
I think it's a combination of playing around and math chops.

Without any mathematical knowledge, you probably couldn't come up with something like the s(i,k,o) function (which, as far as I can tell from just looking/playing around with them briefly, seems to be the function responsible for the tessellation offset), and you might not have thought to define a system like (x=X(N,t), y=Y(N,t), 0<t<1).

Without a nontrivial amount of playing around, you probably wouldn't have found the exact constants used, like (2pi(3^i)), .2/(2^i), etc.--but knowing how altering those affects the end result takes some mathematical knowledge, so it's more guided investigation than random guessing.

[+] meta_pseudo|11 years ago|reply
There are iterated function systems (IFS) for constructing such fractals, Sierpinski gasket is in fact quite common.
[+] joshu|11 years ago|reply
can i extract an svg of this? that would let me CNC it.