FixedValueComparator
FixedValueComparator(num_state_qubits, value, geq=True, i_state=None, i_target=None) GitHub(opens in a new tab)
DEPRECATED. Fixed Value Comparator
Use Terra’s qiskit.circuit.library.IntegerComparator instead.
Operator compares basis states |i>_n against a classically given fixed value L and flips a target qubit if i >= L (or < depending on parameters):
|i>_n|0> –> |i>_n|1> if i >= L else |i>|0>
Operator is based on two’s complement implementation of binary subtraction but only uses carry bits and no actual result bits. If the most significant carry bit (= results bit) is 1, the “>=” condition is True otherwise it is False.
Parameters
- num_state_qubits (int) – number of state qubits, the target qubit comes on top of this
- value (int) – fixed value to compare with
- geq (Optional(bool)) – evaluate “>=” condition of “<” condition
- i_state (Optional(Union(list, numpy.ndarray))) – indices of state qubits in given list of qubits / register, if None, i_state = list(range(num_state_qubits)) is used
- i_target (Optional(int)) – index of target qubit in given list of qubits / register, if None, i_target = num_state_qubits is used
Attributes
num_state_qubits
returns num state qubits
num_target_qubits
Returns the number of target qubits
value
returns value
Methods
build
FixedValueComparator.build(qc, q, q_ancillas=None, params=None)
Adds corresponding sub-circuit to given circuit
Parameters
- qc (QuantumCircuit) – quantum circuit
- q (list) – list of qubits (has to be same length as self._num_qubits)
- q_ancillas (list) – list of ancilla qubits (or None if none needed)
- params (list) – parameters for circuit
build_controlled
FixedValueComparator.build_controlled(qc, q, q_control, q_ancillas=None, use_basis_gates=True)
Adds corresponding controlled sub-circuit to given circuit
Parameters
- qc (QuantumCircuit) – quantum circuit
- q (list) – list of qubits (has to be same length as self._num_qubits)
- q_control (Qubit) – control qubit
- q_ancillas (list) – list of ancilla qubits (or None if none needed)
- use_basis_gates (bool) – use basis gates for expansion of controlled circuit
build_controlled_inverse
FixedValueComparator.build_controlled_inverse(qc, q, q_control, q_ancillas=None, use_basis_gates=True)
Adds controlled inverse of corresponding sub-circuit to given circuit
Parameters
- qc (QuantumCircuit) – quantum circuit
- q (list) – list of qubits (has to be same length as self._num_qubits)
- q_control (Qubit) – control qubit
- q_ancillas (list) – list of ancilla qubits (or None if none needed)
- use_basis_gates (bool) – use basis gates for expansion of controlled circuit
build_controlled_inverse_power
FixedValueComparator.build_controlled_inverse_power(qc, q, q_control, power, q_ancillas=None, use_basis_gates=True)
Adds controlled, inverse, power of corresponding circuit. May be overridden if a more efficient implementation is possible
build_controlled_power
FixedValueComparator.build_controlled_power(qc, q, q_control, power, q_ancillas=None, use_basis_gates=True)
Adds controlled power of corresponding circuit. May be overridden if a more efficient implementation is possible
build_inverse
FixedValueComparator.build_inverse(qc, q, q_ancillas=None)
Adds inverse of corresponding sub-circuit to given circuit
Parameters
- qc (QuantumCircuit) – quantum circuit
- q (list) – list of qubits (has to be same length as self._num_qubits)
- q_ancillas (list) – list of ancilla qubits (or None if none needed)
build_inverse_power
FixedValueComparator.build_inverse_power(qc, q, power, q_ancillas=None)
Adds inverse power of corresponding circuit. May be overridden if a more efficient implementation is possible
build_power
FixedValueComparator.build_power(qc, q, power, q_ancillas=None)
Adds power of corresponding circuit. May be overridden if a more efficient implementation is possible
get_num_qubits
FixedValueComparator.get_num_qubits()
returns number of qubits
get_num_qubits_controlled
FixedValueComparator.get_num_qubits_controlled()
returns number of qubits controlled
required_ancillas
FixedValueComparator.required_ancillas()
returns required ancillas
required_ancillas_controlled
FixedValueComparator.required_ancillas_controlled()
returns required ancillas controlled