NLocal

A list of AncillaQubits in the order that they were added. You should not mutate this.

Return calibration dictionary.

The custom pulse definition of a given gate is of the form {'gate_name': {(qubits, params): schedule}}

A list of Clbits in the order that they were added. You should not mutate this.

The circuit data (instructions and context).

Returns

a list-like object containing the CircuitInstructions for each instruction.

Return type

QuantumCircuitData

The total duration of the circuit, set by a scheduling transpiler pass. Its unit is specified by unit.

Get the entanglement strategy.

Returns

The entanglement strategy, see get_entangler_map() for more detail on how the format is interpreted.

The blocks in the entanglement layers.

Returns

The blocks in the entanglement layers.

Returns whether the circuit is wrapped in nested gates/instructions or flattened.

The global phase of the current circuit scope in radians.

Return the initial state that is added in front of the n-local circuit.

Returns

The initial state.

If barriers are inserted in between the layers or not.

Returns

True, if barriers are inserted in between the layers, False if not.

Default value: 181

Return any associated layout information about the circuit

This attribute contains an optional TranspileLayout object. This is typically set on the output from transpile() or PassManager.run() to retain information about the permutations caused on the input circuit by transpilation.

There are two types of permutations caused by the transpile() function, an initial layout which permutes the qubits based on the selected physical qubits on the Target, and a final layout which is an output permutation caused by SwapGates inserted during routing.

Arbitrary user-defined metadata for the circuit.

Qiskit will not examine the content of this mapping, but it will pass it through the transpiler and reattach it to the output, so you can track your own metadata.

Return the number of ancilla qubits.

The number of real-time classical variables in the circuit marked as captured from an enclosing scope.

This is the length of the iter_captured_vars() iterable. If this is non-zero, num_input_vars must be zero.

Return number of classical bits.

The number of real-time classical variables in the circuit that are declared by this circuit scope, excluding inputs or captures.

This is the length of the iter_declared_vars() iterable.

The number of real-time classical variables in the circuit marked as circuit inputs.

This is the length of the iter_input_vars() iterable. If this is non-zero, num_captured_vars must be zero.

Return the number of layers in the n-local circuit.

Returns

The number of layers in the circuit.

The number of parameter objects in the circuit.

The number of total parameters that can be set to distinct values.

This does not change when the parameters are bound or exchanged for same parameters, and therefore is different from num_parameters which counts the number of unique Parameter objects currently in the circuit.

Returns

The number of parameters originally available in the circuit.

Returns the number of qubits in this circuit.

Returns

The number of qubits.

The number of real-time classical variables in the circuit.

This is the length of the iter_vars() iterable.

Return a list of operation start times.

This attribute is enabled once one of scheduling analysis passes runs on the quantum circuit.

Returns

List of integers representing instruction start times. The index corresponds to the index of instruction in QuantumCircuit.data.

Raises

AttributeError – When circuit is not scheduled.

The parameters used in the underlying circuit.

This includes float values and duplicates.

Examples

>>> # prepare circuit ...
>>> print(nlocal)
     ┌───────┐┌──────────┐┌──────────┐┌──────────┐
q_0: ┤ Ry(1) ├┤ Ry(θ[1]) ├┤ Ry(θ[1]) ├┤ Ry(θ[3]) ├
     └───────┘└──────────┘└──────────┘└──────────┘
>>> nlocal.parameters
{Parameter(θ[1]), Parameter(θ[3])}
>>> nlocal.ordered_parameters
[1, Parameter(θ[1]), Parameter(θ[1]), Parameter(θ[3])]

Returns

The parameters objects used in the circuit.

The parameter bounds for the unbound parameters in the circuit.

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.

The parameters defined in the circuit.

This attribute returns the Parameter objects in the circuit sorted alphabetically. Note that parameters instantiated with a ParameterVector 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 unintuitive 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])
])

Returns

The sorted Parameter objects in the circuit.

The initial points for the parameters. Can be stored as initial guess in optimization.

Returns

The initial values for the parameters, or None, if none have been set.

Default value: 'circuit'

Type: list[QuantumRegister]

A list of the QuantumRegisters in this circuit. You should not mutate this.

A list of Qubits in the order that they were added. You should not mutate this.

The number of times rotation and entanglement block are repeated.

Returns

The number of repetitions.

The blocks in the rotation layers.

Returns

The blocks in the rotation layers.

The unit that duration is specified in.

Type: str

A human-readable name for the circuit.

Type: list[ClassicalRegister]

A list of the ClassicalRegisters in this circuit. You should not mutate this.

add_layer(other, entanglement=None, front=False)

Append another layer to the NLocal.

Parameters

• other (QuantumCircuit |qiskit.circuit.Instruction) – The layer to compose, can be another NLocal, an Instruction or Gate, or a QuantumCircuit.
• entanglement (list[int] | str |list[list[int]] | None) – The entanglement or qubit indices.
• front (bool) – If True, other is appended to the front, else to the back.

Returns

self, such that chained composes are possible.

Raises

TypeError – If other is not compatible, i.e. is no Instruction and does not have a to_instruction method.

Return type

NLocal

assign_parameters(parameters, inplace=False, **kwargs)

Assign parameters to the n-local circuit.

This method also supports passing a list instead of a dictionary. If a list is passed, the list must have the same length as the number of unbound parameters in the circuit. The parameters are assigned in the order of the parameters in ordered_parameters().

Returns

A copy of the NLocal circuit with the specified parameters.

Raises

AttributeError – If the parameters are given as list and do not match the number of parameters.

Return type

QuantumCircuit | None

get_entangler_map(rep_num, block_num, num_block_qubits)

Get the entangler map for in the repetition rep_num and the block block_num.

The entangler map for the current block is derived from the value of self.entanglement. Below the different cases are listed, where i and j denote the repetition number and the block number, respectively, and n the number of qubits in the block.

| None | [[0, ..., n - 1]] | | str (e.g 'full') | the specified connectivity on n qubits | | List[int] | [entanglement] | | List[List[int]] | entanglement | | List[List[List[int]]] | entanglement[i] | | List[List[List[List[int]]]] | entanglement[i][j] | | List[str] | the connectivity specified in entanglement[i] | | List[List[str]] | the connectivity specified in entanglement[i][j] | | Callable[int, str] | same as List[str] | | Callable[int, List[List[int]]] | same as List[List[List[int]]] |

Note that all indices are to be taken modulo the length of the array they act on, i.e. no out-of-bounds index error will be raised but we re-iterate from the beginning of the list.

Parameters

• rep_num (int) – The current repetition we are in.
• block_num (int) – The block number within the entanglement layers.
• num_block_qubits (int) – The number of qubits in the block.

Returns

The entangler map for the current block in the current repetition.

Raises

ValueError – If the value of entanglement could not be cast to a corresponding entangler map.

Return type

Sequence[Sequence[int]]

get_unentangled_qubits()

Get the indices of unentangled qubits in a set.

Returns

The unentangled qubits.

Return type

set[int]

print_settings()

Returns information about the setting.

Returns

The class name and the attributes/parameters of the instance as str.

Return type

str