Add Qudit phase gate, Z_d #194
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unitary/alpha/qudit_gates.py
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| @@ -12,6 +12,14 @@ | |||
| # See the License for the specific language governing permissions and | |||
| # limitations under the License. | |||
| # | |||
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| from typing import ( | |||
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nit: all on one line looks better to me, but I am not sure if the formatter is doing this.
unitary/alpha/qudit_gates.py
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| @@ -51,6 +59,53 @@ def _circuit_diagram_info_(self, args): | |||
| return f"X({self.source_state}_{self.destination_state})" | |||
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| class QuditRzGate(cirq.ops.eigen_gate.EigenGate): | |||
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I would just use cirq.EigenGate in case package names change.
unitary/alpha/qudit_gates.py
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| radians: The phase shift applied to basis d-1, measured in radians. | ||
| """ | ||
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| _eigencomponents: Dict[int, List[Tuple[float, np.ndarray]]] = {} |
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Having _eignencomponents and _eigen_components seems confusing.
| assert np.isclose(phase_rads / np.pi, rz._exponent) | ||
| rz_unitary = cirq.unitary(rz) | ||
| assert np.allclose(cirq.unitary(rz), expected_unitary) | ||
| assert np.allclose(np.eye(len(rz_unitary)), rz_unitary.dot(rz_unitary.T.conj())) |
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I'd feel more comfortable if we had a test on the action of the QuditRzGate too. Can we test the qudit equivalent of HZH and make sure it is equivalent to X?
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Maybe let's make this a follow-up PR until the qudit Hadamard PR issue gets resolved.
unitary/alpha/qudit_gates.py
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| For a qudit of dimensionality d, shifts the phase of |phased_state> by radians. | ||
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| Args: | ||
| dimension: Dimension of the qudits: for instance, a dimension of 3 |
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nit: would probably change the second colon to a period (then capitalize "For")
unitary/alpha/qudit_gates_test.py
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| (np.pi * 4 / 3, np.pi * 2 / 3, 0, 1), | ||
| ], | ||
| ) | ||
| def test_X_HZH_qudit_identity( |
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Why is this function repeated twice?
arxiv.org/abs/2008.00959 describes the Z_d gate as one of three gates that comprise a "universal gate set" for qudit computing.
The commit implements the Z_d gate using cirq.ops.eigen_gate.EigenGate as a base.