tests

qiboteam · Jan 30, 2024 · 373f81c · 373f81c
1 parent 3909820
commit 373f81c
Showing 1 changed file with 114 additions and 58 deletions.
diff --git a/tests/test_quantum_info_entropies.py b/tests/test_quantum_info_entropies.py
@@ -6,9 +6,14 @@
     classical_relative_entropy,
     entanglement_entropy,
     entropy,
+    relative_entropy,
     shannon_entropy,
 )
-from qibo.quantum_info.random_ensembles import random_statevector, random_unitary
+from qibo.quantum_info.random_ensembles import (
+    random_density_matrix,
+    random_statevector,
+    random_unitary,
+)
 
 
 def test_shannon_entropy_errors(backend):
@@ -103,77 +108,54 @@ def test_entropy(backend, base, check_hermitian):
 
 @pytest.mark.parametrize("check_hermitian", [False, True])
 @pytest.mark.parametrize("base", [2, 10, np.e, 5])
-@pytest.mark.parametrize("bipartition", [[0], [1]])
-def test_entanglement_entropy(backend, bipartition, base, check_hermitian):
+def test_relative_entropy(backend, base, check_hermitian):
     with pytest.raises(TypeError):
         state = np.random.rand(2, 3)
         state = backend.cast(state, dtype=state.dtype)
-        test = entanglement_entropy(
-            state,
-            bipartition=bipartition,
-            base=base,
-            check_hermitian=check_hermitian,
-            backend=backend,
+        target = random_density_matrix(2, pure=True, backend=backend)
+        test = relative_entropy(
+            state, target, base=base, check_hermitian=check_hermitian, backend=backend
+        )
+    with pytest.raises(TypeError):
+        target = np.random.rand(2, 3)
+        target = backend.cast(target, dtype=target.dtype)
+        state = random_density_matrix(2, pure=True, backend=backend)
+        test = relative_entropy(
+            state, target, base=base, check_hermitian=check_hermitian, backend=backend
         )
     with pytest.raises(ValueError):
         state = np.array([1.0, 0.0])
         state = backend.cast(state, dtype=state.dtype)
-        test = entanglement_entropy(
-            state,
-            bipartition=bipartition,
-            base=0,
-            check_hermitian=check_hermitian,
-            backend=backend,
+        target = np.array([0.0, 1.0])
+        target = backend.cast(target, dtype=target.dtype)
+        test = relative_entropy(
+            state, target, base=0, check_hermitian=check_hermitian, backend=backend
+        )
+    with pytest.raises(TypeError):
+        state = np.array([1.0, 0.0])
+        state = backend.cast(state, dtype=state.dtype)
+        target = np.array([0.0, 1.0])
+        target = backend.cast(target, dtype=target.dtype)
+        test = relative_entropy(
+            state, target, base=base, check_hermitian="False", backend=backend
         )
-    if backend.__class__.__name__ == "CupyBackend":
-        with pytest.raises(NotImplementedError):
-            state = random_unitary(4, backend=backend)
-            test = entanglement_entropy(
-                state,
-                bipartition=bipartition,
-                base=base,
-                check_hermitian=True,
-                backend=backend,
-            )
-
-    # Bell state
-    state = np.array([1.0, 0.0, 0.0, 1.0]) / np.sqrt(2)
-    state = backend.cast(state, dtype=state.dtype)
-
-    entang_entrop = entanglement_entropy(
-        state,
-        bipartition=bipartition,
-        base=base,
-        check_hermitian=check_hermitian,
-        backend=backend,
-    )
 
-    if base == 2:
-        test = 1.0
-    elif base == 10:
-        test = 0.30102999566398125
-    elif base == np.e:
-        test = 0.6931471805599454
-    else:
-        test = 0.4306765580733931
+    nqubits = 2
+    dims = 2**nqubits
 
-    backend.assert_allclose(entang_entrop, test, atol=PRECISION_TOL)
+    state = random_density_matrix(dims, backend=backend)
+    target = backend.identity_density_matrix(nqubits, normalize=True)
 
-    # Product state
-    state = np.kron(
-        random_statevector(2, backend=backend), random_statevector(2, backend=backend)
-    )
+    print(relative_entropy(state, target, base, check_hermitian, backend))
+    print(entropy(state, base, check_hermitian=check_hermitian, backend=backend))
 
-    entang_entrop = entanglement_entropy(
-        state,
-        bipartition=bipartition,
-        base=base,
-        check_hermitian=check_hermitian,
-        backend=backend,
+    backend.assert_allclose(
+        relative_entropy(state, target, base, check_hermitian, backend),
+        np.log(dims) / np.log(base)
+        - entropy(state, base=base, check_hermitian=check_hermitian, backend=backend),
+        atol=1e-5,
     )
 
-    backend.assert_allclose(entang_entrop, 0.0, atol=PRECISION_TOL)
-
 
 @pytest.mark.parametrize("kind", [None, list])
 @pytest.mark.parametrize("validate", [False, True])
@@ -233,3 +215,77 @@ def test_classical_relative_entropy(backend, base, validate, kind):
     )
 
     backend.assert_allclose(divergence, target, atol=1e-5)
+
+
+@pytest.mark.parametrize("check_hermitian", [False, True])
+@pytest.mark.parametrize("base", [2, 10, np.e, 5])
+@pytest.mark.parametrize("bipartition", [[0], [1]])
+def test_entanglement_entropy(backend, bipartition, base, check_hermitian):
+    with pytest.raises(TypeError):
+        state = np.random.rand(2, 3)
+        state = backend.cast(state, dtype=state.dtype)
+        test = entanglement_entropy(
+            state,
+            bipartition=bipartition,
+            base=base,
+            check_hermitian=check_hermitian,
+            backend=backend,
+        )
+    with pytest.raises(ValueError):
+        state = np.array([1.0, 0.0])
+        state = backend.cast(state, dtype=state.dtype)
+        test = entanglement_entropy(
+            state,
+            bipartition=bipartition,
+            base=0,
+            check_hermitian=check_hermitian,
+            backend=backend,
+        )
+    if backend.__class__.__name__ == "CupyBackend":
+        with pytest.raises(NotImplementedError):
+            state = random_unitary(4, backend=backend)
+            test = entanglement_entropy(
+                state,
+                bipartition=bipartition,
+                base=base,
+                check_hermitian=True,
+                backend=backend,
+            )
+
+    # Bell state
+    state = np.array([1.0, 0.0, 0.0, 1.0]) / np.sqrt(2)
+    state = backend.cast(state, dtype=state.dtype)
+
+    entang_entrop = entanglement_entropy(
+        state,
+        bipartition=bipartition,
+        base=base,
+        check_hermitian=check_hermitian,
+        backend=backend,
+    )
+
+    if base == 2:
+        test = 1.0
+    elif base == 10:
+        test = 0.30102999566398125
+    elif base == np.e:
+        test = 0.6931471805599454
+    else:
+        test = 0.4306765580733931
+
+    backend.assert_allclose(entang_entrop, test, atol=PRECISION_TOL)
+
+    # Product state
+    state = np.kron(
+        random_statevector(2, backend=backend), random_statevector(2, backend=backend)
+    )
+
+    entang_entrop = entanglement_entropy(
+        state,
+        bipartition=bipartition,
+        base=base,
+        check_hermitian=check_hermitian,
+        backend=backend,
+    )
+
+    backend.assert_allclose(entang_entrop, 0.0, atol=PRECISION_TOL)