Function Duff

code/ode/duffing.py:33–36

(t,u,k=0.7,c=0.1,k3=1,
         A=44.5,omega=1.1)

from scipy.integrate import RK45
import matplotlib.pyplot as plt
def Duff(t,u,k=0.7,c=0.1,k3=1,
         A=44.5,omega=1.1):
  return [u[1], -k*u[0]-c*u[1] - 
          k3*u[0]**3+A*np.sin(omega*t)]
T0, Tn = 0, 40
U_0 = [0, 0]
t, u = [], []