# Copyright 2021 Huawei Technologies Co., Ltd
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# ============================================================================
"""RY gate related decompose rule."""
from mindquantum.core import gates
from mindquantum.core.circuit import Circuit
from mindquantum.utils.type_value_check import _check_control_num, _check_input_type
[docs]def cry_decompose(gate: gates.RY):
"""
Decompose controlled :class:`~.core.gates.RY` gate.
Args:
gate (:class:`~.core.gates.RY`): A :class:`~.core.gates.RY` gate with one control qubits.
Returns:
List[:class:`~.core.circuit.Circuit`], all possible decompose solution.
Examples:
>>> from mindquantum.algorithm.compiler import cry_decompose
>>> from mindquantum.core.circuit import Circuit
>>> from mindquantum.core.gates import RY
>>> cry = RY(1).on(1, 0)
>>> origin_circ = Circuit() + cry
>>> decomposed_circ = cry_decompose(cry)[0]
>>> origin_circ
q0: ──────■───────
┃
┏━━━┻━━━┓
q1: ──┨ RY(1) ┠───
┗━━━━━━━┛
>>> decomposed_circ
q0: ────────────────■──────────────────■─────
┃ ┃
┏━━━━━━━━━┓ ┏━┻━┓ ┏━━━━━━━━━━┓ ┏━┻━┓
q1: ──┨ RY(1/2) ┠─┨╺╋╸┠─┨ RY(-1/2) ┠─┨╺╋╸┠───
┗━━━━━━━━━┛ ┗━━━┛ ┗━━━━━━━━━━┛ ┗━━━┛
"""
_check_input_type('gate', gates.RY, gate)
_check_control_num(gate.ctrl_qubits, 1)
circuit = Circuit()
control = gate.ctrl_qubits[0]
target = gate.obj_qubits[0]
circuit += gates.RY(gate.coeff / 2).on(target)
circuit += gates.X.on(target, control)
circuit += gates.RY(-gate.coeff / 2).on(target)
circuit += gates.X.on(target, control)
return [circuit]
def _cnry_frame(ctrl_qubits, obj_qubit, angle):
"""The function used to construct iteratively the circuit of the cnry_decompose compiler.
Args:
ctrl_qubits (List[int]): The remainder ctrl_qubits in current iteration.
obj_qubit (int): The obj_qubit of the RY gate to be decomposed.
angle (:class:'~core.parameterresolver.ParameterResolver`): The rotation angle in current iteration.
Returns:
:class:`~.core.circuit.Circuit`, the decompose solution in current iteration.
"""
circ = Circuit()
if len(ctrl_qubits) == 1:
circ.ry(angle/2, obj_qubit)
circ.x(obj_qubit, ctrl_qubits[0])
circ.ry(-angle/2, obj_qubit)
circ.x(obj_qubit, ctrl_qubits[0])
else:
circ += _cnry_frame(ctrl_qubits[1:], obj_qubit, angle/2)
circ.x(obj_qubit, ctrl_qubits[0])
circ += _cnry_frame(ctrl_qubits[1:], obj_qubit, -angle/2)
circ.x(obj_qubit, ctrl_qubits[0])
return circ
[docs]def cnry_decompose(gate: gates.RY):
"""
Decompose controlled :class:`~.core.gates.RY` gate.
Args:
gate (:class:`~.core.gates.RY`): A :class:`~.core.gates.RY` gate with zero or more control qubits.
Returns:
List[:class:`~.core.circuit.Circuit`], all possible decompose solution.
Examples:
>>> from mindquantum.algorithm.compiler import cnry_decompose
>>> from mindquantum.core.circuit import Circuit
>>> from mindquantum.core.gates import RY
>>> cry = RY(1).on(2, [0, 1])
>>> origin_circ = Circuit() + cry
>>> decomposed_circ = cnry_decompose(cry)[0]
>>> origin_circ
q0: ──────■───────
┃
┃
q1: ──────■───────
┃
┏━━━┻━━━┓
q2: ──┨ RY(1) ┠───
┗━━━━━━━┛
>>> decomposed_circ
q0: ─────────────────────────────────────────■──────────────────────────────────────────■────
┃ ┃
┃ ┃
q1: ────────────────■──────────────────■─────╂──────────────────■─────────────────■─────╂────
┃ ┃ ┃ ┃ ┃ ┃
┏━━━━━━━━━┓ ┏━┻━┓ ┏━━━━━━━━━━┓ ┏━┻━┓ ┏━┻━┓ ┏━━━━━━━━━━┓ ┏━┻━┓ ┏━━━━━━━━━┓ ┏━┻━┓ ┏━┻━┓
q2: ──┨ RY(1/4) ┠─┨╺╋╸┠─┨ RY(-1/4) ┠─┨╺╋╸┠─┨╺╋╸┠─┨ RY(-1/4) ┠─┨╺╋╸┠─┨ RY(1/4) ┠─┨╺╋╸┠─┨╺╋╸┠──
┗━━━━━━━━━┛ ┗━━━┛ ┗━━━━━━━━━━┛ ┗━━━┛ ┗━━━┛ ┗━━━━━━━━━━┛ ┗━━━┛ ┗━━━━━━━━━┛ ┗━━━┛ ┗━━━┛
"""
_check_input_type('gate', gates.RY, gate)
if not gate.ctrl_qubits:
return [Circuit(gate)]
circuit = _cnry_frame(gate.ctrl_qubits, gate.obj_qubits[0], gate.coeff)
return [circuit]
decompose_rules = ['cry_decompose', 'cnry_decompose']
__all__ = decompose_rules