pred_prey_basic_use_of_odeint_to_solve_linear_differential_equations.py

import numpy as np
from scipy.integrate import odeint
import matplotlib.pyplot as plt

t = np.arange(0, 15, 0.1)

a = 0.5
b = 0.5

def tick(y, t):
  rabbits, foxes = y
  return [
    rabbits-a*rabbits*foxes,
    -foxes+b*rabbits*foxes
  ]

sol = odeint(tick, [1, 1], t)

plt.plot(t, sol[:, 0], 'b', label='rabbits(t)')
plt.plot(t, sol[:, 1], 'g', label='foxes(t)')
plt.legend(loc='best')
plt.xlabel('t')
plt.grid()
plt.show()