分形蕨 fractal fern

相关链接

http://www.matrix67.com/blog/archives/500

http://www.cnblogs.com/zhuangzhuang1988/archive/2013/01/03/2843491.html

http://hyry.dip.jp:8000/pydoc/fractal_chaos.html#ifs

http://blog.csdn.net/waynebuaa/article/details/2762977

 

Mathematica code:

a[1] = {{0.85, 0.04}, {-0.04, 0.85}}.# + {0, 1.6} &;

a[2] = {{0.2, -0.26}, {0.23, 0.22}}.# + {0, 1.6} &;

a[3] = {{-0.2, 0.26}, {0.26, 0.24}}.# + {0, 0.44} &;

a[4] = {{0, 0}, {0, 0.16}}.# + {0, 0} &;



iter = a[RandomChoice[{85, 7, 7, 1} -> {1, 2, 3, 4}]][#] &;

pts = NestList[iter, N@{0, 0}, 5 10^5];

Graphics[{Green, AbsolutePointSize@1, Point@pts}]