def linear_equation_fft_solver_3d_test(self, N):
"""
-\Delta u + u = f
u(x, y, z) = sin(x)*sin(y)*sin(z) [0, 2*\pi)^3
"""
def u(p):
x = p[0]
y = p[1]
z = p[2]
return np.sin(x)*np.sin(y)*np.sin(z)
def f(p):
x = p[0]
y = p[1]
z = p[2]
return 4*np.sin(x)*np.sin(y)*np.sin(z)
box = np.array([
[2*np.pi, 0, 0],
[0, 2*np.pi, 0],
[0, 0, 2*np.pi]])
space = FourierSpace(box, 6)
U = space.linear_equation_fft_solver(f)
error = space.error(u, U)
print(error)
def linear_equation_fft_solver_1d_test(self, N):
"""
-\Delta u + u = f
u(x) = sin(x) [0, 2*\pi)
"""
def u(p):
x = p[0]
return np.sin(x)
def f(p):
x = p[0]
return 2*np.sin(x)
box = np.array([[2*np.pi]])
space = FourierSpace(box, N)
U = space.linear_equation_fft_solver(f)
error = space.error(u, U)
print(error)