import unittest import numpy from fdfd_tools import fdtd class BasicTests(): def test_initial_fields(self): # Make sure initial fields didn't change e0 = self.es[0] h0 = self.hs[0] mask = self.src_mask self.assertEqual(e0[mask], self.j_mag / self.epsilon[mask]) self.assertFalse(e0[~mask].any()) self.assertFalse(h0.any()) def test_initial_energy(self): e0 = self.es[0] h0 = self.hs[0] h1 = self.hs[1] mask = self.src_mask[1] dxes = self.dxes if self.dxes is not None else tuple(tuple(numpy.ones(s) for s in e0.shape[1:]) for _ in range(2)) dV = numpy.prod(numpy.meshgrid(*dxes[0], indexing='ij'), axis=0) u0 = self.j_mag * self.j_mag / self.epsilon[self.src_mask] * dV[mask] args = {'dxes': self.dxes, 'epsilon': self.epsilon} # Make sure initial energy and E dot J are correct energy0 = fdtd.energy_estep(h0=h0, e1=e0, h2=self.hs[1], **args) e_dot_j_0 = fdtd.delta_energy_j(j0=(e0 - 0) * self.epsilon, e1=e0, dxes=self.dxes) self.assertEqual(energy0[mask], u0) self.assertFalse(energy0[~mask].any()) self.assertEqual(e_dot_j_0[mask], u0) self.assertFalse(e_dot_j_0[~mask].any()) def test_energy_conservation(self): e0 = self.es[0] u0 = fdtd.delta_energy_j(j0=(e0 - 0) * self.epsilon, e1=e0, dxes=self.dxes).sum() args = {'dxes': self.dxes, 'epsilon': self.epsilon} for ii in range(1, 8): with self.subTest(i=ii): u_hstep = fdtd.energy_hstep(e0=self.es[ii-1], h1=self.hs[ii], e2=self.es[ii], **args) u_estep = fdtd.energy_estep(h0=self.hs[ii], e1=self.es[ii], h2=self.hs[ii + 1], **args) self.assertTrue(numpy.allclose(u_hstep.sum(), u0)) self.assertTrue(numpy.allclose(u_estep.sum(), u0)) def test_poynting(self): args = {'dxes': self.dxes, 'epsilon': self.epsilon} u_eprev = None for ii in range(1, 8): with self.subTest(i=ii): u_hstep = fdtd.energy_hstep(e0=self.es[ii-1], h1=self.hs[ii], e2=self.es[ii], **args) u_estep = fdtd.energy_estep(h0=self.hs[ii], e1=self.es[ii], h2=self.hs[ii + 1], **args) du_half_h2e = u_estep - u_hstep div_s_h2e = self.dt * fdtd.poynting_divergence(e=self.es[ii], h=self.hs[ii], dxes=self.dxes) self.assertTrue(numpy.allclose(du_half_h2e, -div_s_h2e)) if u_eprev is None: u_eprev = u_estep continue # previous half-step du_half_e2h = u_hstep - u_eprev div_s_e2h = self.dt * fdtd.poynting_divergence(e=self.es[ii-1], h=self.hs[ii], dxes=self.dxes) self.assertTrue(numpy.allclose(du_half_e2h, -div_s_e2h)) u_eprev = u_estep class Basic2DNoDXOnlyVacuum(unittest.TestCase, BasicTests): def setUp(self): shape = [3, 5, 5, 1] self.dt = 0.5 self.epsilon = numpy.ones(shape, dtype=float) self.j_mag = 32 self.dxes = None self.src_mask = numpy.zeros_like(self.epsilon, dtype=bool) self.src_mask[1, 2, 2, 0] = True e = numpy.zeros_like(self.epsilon) h = numpy.zeros_like(self.epsilon) e[self.src_mask] = self.j_mag / self.epsilon[self.src_mask] self.es = [e] self.hs = [h] eh2h = fdtd.maxwell_h(dt=self.dt, dxes=self.dxes) eh2e = fdtd.maxwell_e(dt=self.dt, dxes=self.dxes) for _ in range(9): e = e.copy() h = h.copy() eh2h(e, h) eh2e(e, h, self.epsilon) self.es.append(e) self.hs.append(h) class Basic3DUniformDXOnlyVacuum(unittest.TestCase, BasicTests): def setUp(self): shape = [3, 5, 5, 5] self.dt = 0.33 self.epsilon = numpy.ones(shape, dtype=float) self.j_mag = 32 self.dxes = tuple(tuple(numpy.ones(s) for s in shape[1:]) for _ in range(2)) self.src_mask = numpy.zeros_like(self.epsilon, dtype=bool) self.src_mask[1, 2, 2, 0] = True e = numpy.zeros_like(self.epsilon) h = numpy.zeros_like(self.epsilon) e[self.src_mask] = self.j_mag / self.epsilon[self.src_mask] self.es = [e] self.hs = [h] eh2h = fdtd.maxwell_h(dt=self.dt, dxes=self.dxes) eh2e = fdtd.maxwell_e(dt=self.dt, dxes=self.dxes) for _ in range(9): e = e.copy() h = h.copy() eh2h(e, h) eh2e(e, h, self.epsilon) self.es.append(e) self.hs.append(h) class Basic3DUniformDX(unittest.TestCase, BasicTests): def setUp(self): shape = [3, 5, 5, 5] self.dt = 0.33 self.epsilon = numpy.full(shape, 2, dtype=float) self.j_mag = 32 self.dxes = tuple(tuple(numpy.ones(s) for s in shape[1:]) for _ in range(2)) self.src_mask = numpy.zeros_like(self.epsilon, dtype=bool) self.src_mask[1, 2, 2, 0] = True e = numpy.zeros_like(self.epsilon) h = numpy.zeros_like(self.epsilon) e[self.src_mask] = self.j_mag / self.epsilon[self.src_mask] self.es = [e] self.hs = [h] eh2h = fdtd.maxwell_h(dt=self.dt, dxes=self.dxes) eh2e = fdtd.maxwell_e(dt=self.dt, dxes=self.dxes) for _ in range(9): e = e.copy() h = h.copy() eh2h(e, h) eh2e(e, h, self.epsilon) self.es.append(e) self.hs.append(h)