QAOAAnsatz¶
-
class
QAOAAnsatz(cost_operator=None, reps=1, initial_state=None, mixer_operator=None, name='QAOA')[source]¶ Bases:
qiskit.circuit.library.evolved_operator_ansatz.EvolvedOperatorAnsatzA generalized QAOA quantum circuit with a support of custom initial states and mixers.
References
- [1]: Farhi et al., A Quantum Approximate Optimization Algorithm.
- Parameters
cost_operator (OperatorBase, optional) – The operator representing the cost of the optimization problem, denoted as \(U(C, \gamma)\) in the original paper. Must be set either in the constructor or via property setter.
reps (int) – The integer parameter p, which determines the depth of the circuit, as specified in the original paper, default is 1.
initial_state (QuantumCircuit, optional) – An optional initial state to use. If None is passed then a set of Hadamard gates is applied as an initial state to all qubits.
mixer_operator (OperatorBase or QuantumCircuit, optional) – An optional custom mixer to use instead of the global X-rotations, denoted as \(U(B, \beta)\) in the original paper. Can be an operator or an optionally parameterized quantum circuit.
name (str) – A name of the circuit, default ‘qaoa’
Attributes
-
ancillas¶ Returns a list of ancilla bits in the order that the registers were added.
-
calibrations¶ Return calibration dictionary.
- The custom pulse definition of a given gate is of the form
{‘gate_name’: {(qubits, params): schedule}}
-
clbits¶ Returns a list of classical bits in the order that the registers were added.
-
cost_operator¶ Returns an operator representing the cost of the optimization problem.
- Returns
cost operator.
- Return type
-
data¶
-
evolution¶ The evolution converter used to compute the evolution.
- Returns
The evolution converter used to compute the evolution.
- Return type
-
extension_lib= 'include "qelib1.inc";'¶
-
global_phase¶ Return the global phase of the circuit in radians.
-
header= 'OPENQASM 2.0;'¶
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initial_state¶ Returns an optional initial state as a circuit
- Return type
Optional[QuantumCircuit]
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instances= 16¶
-
metadata¶ The user provided metadata associated with the circuit
The metadata for the circuit is a user provided
dictof metadata for the circuit. It will not be used to influence the execution or operation of the circuit, but it is expected to be passed between all transforms of the circuit (ie transpilation) and that providers will associate any circuit metadata with the results it returns from execution of that circuit.
-
mixer_operator¶ Returns an optional mixer operator expressed as an operator or a quantum circuit.
- Returns
mixer operator or circuit.
- Return type
OperatorBase or QuantumCircuit, optional
-
num_ancillas¶ Return the number of ancilla qubits.
-
num_clbits¶ Return number of classical bits.
-
num_parameters¶ - Return type
int
-
num_qubits¶ Return the number of qubits, specified by the size of the cost operator.
- Return type
int
-
operators¶ The operators that are evolved in this circuit.
- Returns
- The operators to be evolved (and circuits)
in this ansatz.
- Return type
List[Union[OperatorBase, QuantumCircuit]]
-
parameter_bounds¶ Parameter bounds.
- Returns: A list of pairs indicating the bounds, as (lower, upper). None indicates
an unbounded parameter in the corresponding direction. If None is returned, problem is fully unbounded or is not built yet.
- Return type
List[Tuple[float,float]]
-
parameters¶ Get the
Parameterobjects in the circuit.- Return type
Set[Parameter]- Returns
A set containing the unbound circuit parameters.
-
preferred_init_points¶ Getter of preferred initial points based on the given initial state.
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prefix= 'circuit'¶
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qregs¶ A list of the quantum registers associated with the circuit.
-
qubits¶ Returns a list of quantum bits in the order that the registers were added.
-
reps¶ Returns the reps parameter, which determines the depth of the circuit.
- Return type
int