# The Barnsley Fern is a fractal named after the British mathematician 
# Michael Barnsley who first described it in his book Fractals Everywhere.
# He made it to resemble the Black Spleenwort, Asplenium adiantum-nigrum.

import numpy as np
import matplotlib.pyplot as plt

N=1000000

x=0.0
y=0.0
z=np.zeros((2,N))

for j in range(N):

    rnd=np.random.random()

    if rnd<=0.85:
        # 85%
        x2=0.85*x+0.04*y
        y2=-0.04*x+0.85*y+1.6
    elif rnd<=0.92:
        # 7%
        x2=0.2*x-0.26*y
        y2=0.23*x+0.22*y+1.6
    elif rnd<=0.99:
        # 7%
        x2=-0.15*x+0.28*y
        y2=0.26*x+0.24*y+0.44
    else:
        # 1%
        x2=0.0
        y2=0.16*y

    x=x2
    y=y2
    z[:,j]=x,y

plt.plot(z[0,:],z[1,:],linestyle="None",marker=".",markersize=1,color="#00FF00")
plt.show()