fixes

pennylane/spin/__init__.py

@@ -20,6 +20,6 @@
     fermi_hubbard,
     heisenberg,
     kitaev,
+    spin_hamiltonian,
     transverse_ising,
-    custom_hamiltonian_from_lattice,
 )

tests/spin/test_spin_hamiltonian.py

@@ -23,11 +23,11 @@
 from pennylane import I, X, Y, Z
 from pennylane.spin import (
     Lattice,
-    custom_hamiltonian_from_lattice,
     fermi_hubbard,
     heisenberg,
     kitaev,
     transverse_ising,
+    spin_hamiltonian
 )
 
 pytestmark = pytest.mark.usefixtures("new_opmath_only")
@@ -907,10 +907,32 @@ def test_kitaev_hamiltonian(n_cells, j, boundary_condition, expected_ham):
             ),
         ),
     ],
+    ("lattice", "expected_ham"),
+    [
+        (
+            Lattice(
+                n_cells=[2, 2],
+                vectors=[[1, 0], [0, 1]],
+                positions=[[0, 0], [1, 5]],
+                boundary_condition=False,
+                custom_edges=[[(0, 1), ("XX", 0.5)], [(1, 2), ("YY", 0.6)], [(1, 4), ("ZZ", 0.7)]],
+            ),
+            (
+                0.5 * (X(0) @ X(1))
+                + 0.5 * (X(2) @ X(3))
+                + 0.5 * (X(4) @ X(5))
+                + 0.5 * (X(6) @ X(7))
+                + 0.6 * (Y(1) @ Y(2))
+                + 0.6 * (Y(5) @ Y(6))
+                + 0.7 * (Z(1) @ Z(4))
+                + 0.7 * (Z(3) @ Z(6))
+            ),
+        ),
+    ],
 )
 def test_custom_hamiltonian(lattice, expected_ham):
     r"""Test that the correct Hamiltonian is generated"""
-    custom_ham = custom_hamiltonian_from_lattice(lattice=lattice)
+    custom_ham = spin_hamiltonian(lattice=lattice)
 
     qml.assert_equal(custom_ham, expected_ham)