Lorenz attractor


In [1]:
import numpy as np
import k3d

plot = k3d.plot()
plot.display()



In [2]:
def lorenz(x, y, z, s=10, r=28, b=2.667):
    x_dot = s*(y - x)
    y_dot = r*x - y - x*z
    z_dot = x*y - b*z
    return x_dot, y_dot, z_dot


dt = 0.01
stepCnt = 10000

# Need one more for the initial values
xs = np.empty((stepCnt + 1,), dtype=np.float32)
ys = np.empty((stepCnt + 1,), dtype=np.float32)
zs = np.empty((stepCnt + 1,), dtype=np.float32)

# Setting initial values
xs[0], ys[0], zs[0] = (0., 1., 1.05)

# Stepping through "time".
for i in range(stepCnt):
    # Derivatives of the X, Y, Z state
    x_dot, y_dot, z_dot = lorenz(xs[i], ys[i], zs[i])
    xs[i + 1] = xs[i] + (x_dot * dt)
    ys[i + 1] = ys[i] + (y_dot * dt)
    zs[i + 1] = zs[i] + (z_dot * dt)
    
    
line = k3d.line(np.vstack([xs,ys,zs]).T)

plot += line