improve plane wave H integration test (#56)

Author: Spaceenter

src/fermilib/utils/_plane_wave_hamiltonian_test.py

@@ -69,21 +69,25 @@ def test_inverse_fourier_transform_2d(self):
         self.assertTrue(normal_ordered(h_dual_basis_t).isclose(
             normal_ordered(h_plane_wave)))
 
-    def test_u_operator_integration(self):
-        grid = Grid(dimensions=1, scale=1.0, length=3)
+    def test_plane_wave_hamiltonian_integration(self):
+        length_set = [3, 4]
         spinless_set = [True, False]
         geometry = [('H', (0,)), ('H', (0.8,))]
-        for spinless in spinless_set:
-            u_plane_wave = plane_wave_u_operator(grid, geometry, spinless)
-            u_dual_basis = dual_basis_u_operator(grid, geometry, spinless)
-            jw_u_plane_wave = jordan_wigner(u_plane_wave)
-            jw_u_dual_basis = jordan_wigner(u_dual_basis)
-            u_plane_wave_spectrum = eigenspectrum(jw_u_plane_wave)
-            u_dual_basis_spectrum = eigenspectrum(jw_u_dual_basis)
+        for l in length_set:
+            for spinless in spinless_set:
+                grid = Grid(dimensions=1, scale=1.0, length=l)
+                h_plane_wave = plane_wave_hamiltonian(grid, geometry, spinless,
+                                                      True)
+                h_dual_basis = plane_wave_hamiltonian(grid, geometry, spinless,
+                                                      False)
+                jw_h_plane_wave = jordan_wigner(h_plane_wave)
+                jw_h_dual_basis = jordan_wigner(h_dual_basis)
+                h_plane_wave_spectrum = eigenspectrum(jw_h_plane_wave)
+                h_dual_basis_spectrum = eigenspectrum(jw_h_dual_basis)
 
-            diff = numpy.amax(numpy.absolute(
-                u_plane_wave_spectrum - u_dual_basis_spectrum))
-            self.assertAlmostEqual(diff, 0)
+                diff = numpy.amax(numpy.absolute(
+                    h_plane_wave_spectrum - h_dual_basis_spectrum))
+                self.assertAlmostEqual(diff, 0)
 
 
 # Run test.