qiskit.providers.aer.extensions.SnapshotExpectationValue¶

class SnapshotExpectationValue(label, op, single_shot=False, variance=False)[Quellcode]¶

Snapshot instruction for supported methods of Qasm simulator.

Create an expectation value snapshot instruction.

Parameter

label (str) – the snapshot label.
op (Operator) – operator to snapshot.
single_shot (bool) – return list for each shot rather than average [Default: False]
variance (bool) – compute variance of values [Default: False]

Verursacht

ExtensionError – if snapshot is invalid.

Bemerkung

This instruction will be deprecated after the qiskit-aer 0.8 release. It has been superseded by the qiskit.providers.aer.library.SaveExpectationValue and qiskit.providers.aer.library.SaveExpectationValueVariance instructions.

__init__(label, op, single_shot=False, variance=False)[Quellcode]¶

Create an expectation value snapshot instruction.

Parameter

label (str) – the snapshot label.
op (Operator) – operator to snapshot.
single_shot (bool) – return list for each shot rather than average [Default: False]
variance (bool) – compute variance of values [Default: False]

Verursacht

ExtensionError – if snapshot is invalid.

Bemerkung

This instruction will be deprecated after the qiskit-aer 0.8 release. It has been superseded by the qiskit.providers.aer.library.SaveExpectationValue and qiskit.providers.aer.library.SaveExpectationValueVariance instructions.

Methods

`__init__`(label, op[, single_shot, variance])	Create an expectation value snapshot instruction.
`add_decomposition`(decomposition)	Add a decomposition of the instruction to the SessionEquivalenceLibrary.
`assemble`()	Assemble a QasmQobjInstruction for snapshot_expectation_value.
`broadcast_arguments`(qargs, cargs)	Validation of the arguments.
`c_if`(classical, val)	Add classical condition on register classical and value val.
`copy`([name])	Copy of the instruction.
`define_snapshot_register`(circuit[, label, …])	Defines qubits to snapshot for all snapshot methods
`inverse`()	Special case.
`is_parameterized`()	Return True .IFF.
`mirror`()	DEPRECATED: use instruction.reverse_ops().
`qasm`()	Return a default OpenQASM string for the instruction.
`repeat`(n)	Creates an instruction with gate repeated n amount of times.
`reverse_ops`()	For a composite instruction, reverse the order of sub-instructions.
`soft_compare`(other)	Soft comparison between gates.
`validate_parameter`(parameter)	Instruction parameters has no validation or normalization.

Attributes

`decompositions`	Get the decompositions of the instruction from the SessionEquivalenceLibrary.
`definition`	Return definition in terms of other basic gates.
`duration`	Get the duration.
`label`	Return snapshot label
`params`	return instruction params.
`snapshot_type`	Return snapshot type
`unit`	Get the time unit of duration.

add_decomposition(decomposition)¶: Add a decomposition of the instruction to the SessionEquivalenceLibrary.

assemble()[Quellcode]¶: Assemble a QasmQobjInstruction for snapshot_expectation_value.

broadcast_arguments(qargs, cargs)¶

Validation of the arguments.

Parameter

qargs (List) – List of quantum bit arguments.
cargs (List) – List of classical bit arguments.

Yields

Tuple(List, List) – A tuple with single arguments.

Verursacht

CircuitError – If the input is not valid. For example, the number of arguments does not match the gate expectation.

c_if(classical, val)¶: Add classical condition on register classical and value val.

copy(name=None)¶

Copy of the instruction.

Parameter

name (str) – name to be given to the copied circuit, if None then the name stays the same.

Rückgabe

a copy of the current instruction, with the name: updated if it was provided

Rückgabetyp

qiskit.circuit.Instruction

property decompositions¶: Get the decompositions of the instruction from the SessionEquivalenceLibrary.

static define_snapshot_register(circuit, label=None, qubits=None)¶: Defines qubits to snapshot for all snapshot methods

property definition¶: Return definition in terms of other basic gates.

property duration¶: Get the duration.

inverse()¶: Special case. Return self.

is_parameterized()¶: Return True .IFF. instruction is parameterized else False

property label¶: Return snapshot label

mirror()¶

DEPRECATED: use instruction.reverse_ops().

Rückgabe

a new instruction with sub-instructions: reversed.

Rückgabetyp

qiskit.circuit.Instruction

property params¶: return instruction params.

qasm()¶

Return a default OpenQASM string for the instruction.

Derived instructions may override this to print in a different format (e.g. measure q[0] -> c[0];).

repeat(n)¶

Creates an instruction with gate repeated n amount of times.

Parameter: n (int) – Number of times to repeat the instruction
Rückgabe: Containing the definition.
Rückgabetyp: qiskit.circuit.Instruction
Verursacht: CircuitError – If n < 1.

reverse_ops()¶

For a composite instruction, reverse the order of sub-instructions.

This is done by recursively reversing all sub-instructions. It does not invert any gate.

Rückgabe

a new instruction with: sub-instructions reversed.

Rückgabetyp

qiskit.circuit.Instruction

property snapshot_type¶: Return snapshot type

soft_compare(other)¶

Soft comparison between gates. Their names, number of qubits, and classical bit numbers must match. The number of parameters must match. Each parameter is compared. If one is a ParameterExpression then it is not taken into account.

Parameter: other (instruction) – other instruction.
Rückgabe: are self and other equal up to parameter expressions.
Rückgabetyp: bool

property unit¶: Get the time unit of duration.

validate_parameter(parameter)¶: Instruction parameters has no validation or normalization.