Fixing PEC boundary condition handling

Author: momchil-flex

tests/test_plugins/test_mode_solver.py

@@ -1241,7 +1241,7 @@ def test_high_order_mode_normalization():
 def test_mode_solver_angle_symmetry():
     # Angle to test
     theta = np.pi / 180
-    theta = np.pi / 6
+    # theta = np.pi / 6
 
     # Other parameters
     plane = td.Box(center=(0, 0, 0), size=(5, 0, 8))
@@ -1269,7 +1269,7 @@ def test_mode_solver_angle_symmetry():
         # grid_spec=td.GridSpec.uniform(dl=0.04),
         structures=[wg],
         run_time=1e-12,
-        symmetry=(0, 0, -1),
+        symmetry=(-1, 0, 0),
         sources=[src],
         # medium=td.Medium(permittivity=4.5),
     )
@@ -1295,13 +1295,13 @@ def test_mode_solver_angle_symmetry():
     ms_angle = ms.updated_copy(mode_spec=mode_spec, simulation=simulation)
     modes_angle = ms_angle.solve()
 
-    import matplotlib.pyplot as plt
+    # import matplotlib.pyplot as plt
 
-    fig, ax = plt.subplots(1, 3)
-    simulation.plot(x=0, ax=ax[0])
-    simulation.plot(y=0, ax=ax[1])
-    simulation.plot(z=0, ax=ax[2])
-    plt.show()
+    # fig, ax = plt.subplots(1, 3)
+    # simulation.plot(x=0, ax=ax[0])
+    # simulation.plot(y=0, ax=ax[1])
+    # simulation.plot(z=0, ax=ax[2])
+    # plt.show()
 
     # Plot the mode_index = 0 mode for both
     _, ax = plt.subplots(1, 2)
@@ -1312,7 +1312,10 @@ def test_mode_solver_angle_symmetry():
     print(modes_zero.n_complex.values)
     print(modes_angle.n_complex.values)
 
-    assert np.allclose(modes_zero.n_complex.values, modes_angle.n_complex.values, atol=3e-2)
+    # Modes with and without an angle are close
+    assert np.allclose(modes_zero.n_complex.values, modes_angle.n_complex.values, atol=2e-2)
+    # Modes with angle (tensorial mode solver) have a small k_eff
+    assert np.all(np.abs(modes_angle.k_eff) < 1e-10)
 
 
 def test_gauge_robustness():
@@ -1364,3 +1367,7 @@ def test_translated_dot():
 
     assert np.allclose(data2.outer_dot(data_translated), data2.outer_dot(data2), atol=atol)
     assert np.allclose(data_translated.outer_dot(data2), data2.outer_dot(data2), atol=atol)
+
+
+if __name__ == "__main__":
+    test_mode_solver_angle_symmetry()

tidy3d/components/mode/derivatives.py

@@ -261,6 +261,9 @@ def make_cxf(dls, shape, pmc):
 
 def make_cxb(dls, shape, pmc):
     """Backward colocation in x."""
+
+    # return make_cxf(dls, shape, pmc).T
+
     import scipy.sparse as sp
 
     Nx, Ny = shape
@@ -307,6 +310,9 @@ def make_cyf(dls, shape, pmc):
 
 def make_cyb(dls, shape, pmc):
     """Backward colocation in y."""
+
+    # return make_cyf(dls, shape, pmc).T
+
     import scipy.sparse as sp
 
     Nx, Ny = shape