def test_ForwardEuler_against_linear_solution():

"""Use knowledge of an exact numerical solution for testing."""

def f(u, t):

return 0.2 + (u - u_exact(t))**4

def u_exact(t):

return 0.2*t + 3

u, t = ForwardEuler(f, U0=u_exact(0), T=3, n=5)

u_e = u_exact(t)

error = np.abs(u_e - u).max()

success = error < 1E-14

assert success, ’|exact - u| = %g != 0’ % error