Skip to content

Instantly share code, notes, and snippets.

Embed
What would you like to do?
Python script to draw a lorenz attractor with Euler's method.
#! /usr/local/bin/python3.6
"""
Lorenz attractor (Euler method)
"""
import sys
import traceback
import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D
class LorenzAttractorEuler:
DT = 1e-3 # Differential interval
STEP = 100000 # Time step count
X_0, Y_0, Z_0 = 1, 1, 1 # Initial values of x, y, z
def __init__(self):
self.res = [[], [], []]
def exec(self):
""" Loranz attractor (Euler method) execution """
try:
xyz = [self.X_0, self.Y_0, self.Z_0]
for _ in range(self.STEP):
l = self.__lorenz(xyz)
for i in range(3):
xyz[i] += self.DT * l[i]
self.res[i].append(xyz[i])
self.__plot()
except Exception as e:
raise
def __lorenz(self, xyz, p=10, r=28, b=8/3.0):
""" Lorenz equation
:param list xyz
:param float p
:param float r
:param float b
:return list xyz
"""
try:
return [
-p * xyz[0] + p * xyz[1],
-xyz[0] * xyz[2] + r * xyz[0] - xyz[1],
xyz[0] * xyz[1] - b * xyz[2]
]
except Exception as e:
raise
def __plot(self):
""" Protting """
try:
fig = plt.figure()
ax = Axes3D(fig)
ax.set_xlabel("x")
ax.set_ylabel("y")
ax.set_zlabel("z")
ax.set_title("Lorenz attractor (Euler method)")
ax.plot(self.res[0], self.res[1], self.res[2], lw=1)
#plt.show()
plt.savefig("lorenz_attractor_euler.png")
except Exception as e:
raise
if __name__ == '__main__':
try:
obj = LorenzAttractorEuler()
obj.exec()
except Exception as e:
traceback.print_exc()
sys.exit(1)
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
You can’t perform that action at this time.