PhaseOracle¶
- class PhaseOracle(expression, synthesizer=None)[código fonte]¶
Bases:
QuantumCircuit
Phase Oracle.
The Phase Oracle object constructs circuits for any arbitrary input logical expressions. A logical expression is composed of logical operators & (AND), | (OR), ~ (NOT), and ^ (XOR). as well as symbols for literals (variables). For example, “a & b”, and (v0 | ~v1) & (~v2 & v3) are both valid string representation of boolean logical expressions.
For convenience, this oracle, in addition to parsing arbitrary logical expressions, also supports input strings in the DIMACS CNF format, which is the standard format for specifying SATisfiability (SAT) problem instances in Conjunctive Normal Form (CNF), which is a conjunction of one or more clauses, where a clause is a disjunction of one or more literals. See
qiskit.circuit.library.phase_oracle.PhaseOracle.from_dimacs_file()
.From 16 variables on, possible performance issues should be expected when using the default synthesizer.
Creates a PhaseOracle object
- Parâmetros
expression (
Union
[str
,ClassicalElement
]) – A Python-like boolean expression.synthesizer (
Optional
[Callable
[[BooleanExpression
],QuantumCircuit
]]) – Optional. A function to convert a BooleanExpression into a QuantumCircuit If None is provided, Tweedledum’s pkrm_synth with phase_esop will be used.
Methods Defined Here
Evaluate the oracle on a bitstring.
Create a PhaseOracle from the string in the DIMACS format.
Attributes
- ancillas¶
Returns a list of ancilla bits in the order that the registers were added.
- Tipo de retorno
List
[AncillaQubit
]
- calibrations¶
Return calibration dictionary.
- The custom pulse definition of a given gate is of the form
{“gate_name”: {(qubits, params): schedule}}
- Tipo de retorno
dict
- clbits¶
Returns a list of classical bits in the order that the registers were added.
- Tipo de retorno
List
[Clbit
]
- data¶
Return the circuit data (instructions and context).
- Retorno
a list-like object containing the
CircuitInstruction
s for each instruction.- Tipo de retorno
QuantumCircuitData
- extension_lib = 'include "qelib1.inc";'¶
- global_phase¶
Return the global phase of the circuit in radians.
- Tipo de retorno
Union
[ParameterExpression
,float
]
- header = 'OPENQASM 2.0;'¶
- instances = 94¶
- metadata¶
The user provided metadata associated with the circuit
The metadata for the circuit is a user provided
dict
of 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.- Tipo de retorno
dict
- num_ancillas¶
Return the number of ancilla qubits.
- Tipo de retorno
int
- num_clbits¶
Return number of classical bits.
- Tipo de retorno
int
- num_parameters¶
The number of parameter objects in the circuit.
- Tipo de retorno
int
- num_qubits¶
Return number of qubits.
- Tipo de retorno
int
- op_start_times¶
Return a list of operation start times.
This attribute is enabled once one of scheduling analysis passes runs on the quantum circuit.
- Tipo de retorno
List
[int
]- Retorno
List of integers representing instruction start times. The index corresponds to the index of instruction in
QuantumCircuit.data
.- Levanta
AttributeError – When circuit is not scheduled.
- parameters¶
The parameters defined in the circuit.
This attribute returns the
Parameter
objects in the circuit sorted alphabetically. Note that parameters instantiated with aParameterVector
are still sorted numerically.Examples
The snippet below shows that insertion order of parameters does not matter.
>>> from qiskit.circuit import QuantumCircuit, Parameter >>> a, b, elephant = Parameter("a"), Parameter("b"), Parameter("elephant") >>> circuit = QuantumCircuit(1) >>> circuit.rx(b, 0) >>> circuit.rz(elephant, 0) >>> circuit.ry(a, 0) >>> circuit.parameters # sorted alphabetically! ParameterView([Parameter(a), Parameter(b), Parameter(elephant)])
Bear in mind that alphabetical sorting might be unituitive when it comes to numbers. The literal «10» comes before «2» in strict alphabetical sorting.
>>> from qiskit.circuit import QuantumCircuit, Parameter >>> angles = [Parameter("angle_1"), Parameter("angle_2"), Parameter("angle_10")] >>> circuit = QuantumCircuit(1) >>> circuit.u(*angles, 0) >>> circuit.draw() ┌─────────────────────────────┐ q: ┤ U(angle_1,angle_2,angle_10) ├ └─────────────────────────────┘ >>> circuit.parameters ParameterView([Parameter(angle_1), Parameter(angle_10), Parameter(angle_2)])
To respect numerical sorting, a
ParameterVector
can be used.>>> from qiskit.circuit import QuantumCircuit, Parameter, ParameterVector >>> x = ParameterVector("x", 12) >>> circuit = QuantumCircuit(1) >>> for x_i in x: ... circuit.rx(x_i, 0) >>> circuit.parameters ParameterView([ ParameterVectorElement(x[0]), ParameterVectorElement(x[1]), ParameterVectorElement(x[2]), ParameterVectorElement(x[3]), ..., ParameterVectorElement(x[11]) ])
- Tipo de retorno
ParameterView
- Retorno
The sorted
Parameter
objects in the circuit.
- prefix = 'circuit'¶