plot_two_lines.py

from math import log
from matplotlib import pyplot as plt
import numpy as np

def fn_a(n):
  return 64*n*log(n)

def fn_b(n):
  return 8*n*n

x = np.arange(1, 100)
plt.plot(x, [fn_a(y) for y in x])
plt.plot(x, [fn_b(y) for y in x])
plt.show()