qiskit.aqua.operators.converters.AbelianGrouper
class AbelianGrouper(traverse=True)
The AbelianGrouper converts SummedOps into a sum of Abelian sums.
Meaning, it will traverse the Operator, and when it finds a SummedOp, it will evaluate which of the summed sub-Operators commute with one another. It will then convert each of the groups of commuting Operators into their own SummedOps, and return the sum-of-commuting-SummedOps. This is particularly useful for cases where mutually commuting groups can be handled similarly, as in the case of Pauli Expectations, where commuting Paulis have the same diagonalizing circuit rotation, or Pauli Evolutions, where commuting Paulis can be diagonalized together.
Parameters
traverse (bool) – Whether to convert only the Operator passed to convert, or traverse down that Operator.
__init__
__init__(traverse=True)
Parameters
traverse (bool) – Whether to convert only the Operator passed to convert, or traverse down that Operator.
Methods
__init__([traverse]) | type traversebool |
convert(operator) | Check if operator is a SummedOp, in which case covert it into a sum of mutually commuting sums, or if the Operator contains sub-Operators and traverse is True, attempt to convert any sub-Operators. |
group_subops(list_op[, fast, use_nx]) | Given a ListOp, attempt to group into Abelian ListOps of the same type. |
convert
convert(operator)
Check if operator is a SummedOp, in which case covert it into a sum of mutually commuting sums, or if the Operator contains sub-Operators and traverse is True, attempt to convert any sub-Operators.
Parameters
operator (OperatorBase) – The Operator to attempt to convert.
Return type
OperatorBase
Returns
The converted Operator.
group_subops
classmethod group_subops(list_op, fast=None, use_nx=None)
Given a ListOp, attempt to group into Abelian ListOps of the same type.
Parameters
- list_op (
ListOp) – The Operator to group into Abelian groups - fast (
Optional[bool]) – Ignored - parameter will be removed in future release - use_nx (
Optional[bool]) – Ignored - parameter will be removed in future release
Return type
ListOp
Returns
The grouped Operator.
Raises
AquaError – If any of list_op’s sub-ops is not PauliOp.