def statefn_replacement_fn(
cob_instr_op: PrimitiveOp,
dest_pauli_op: Union[PauliOp, PauliSumOp, ListOp]) -> OperatorBase:
r"""
A built-in convenience replacement function which produces state functions
isomorphic to an ``OperatorStateFn`` state function holding the origin ``PauliOp``.
Args:
cob_instr_op: The basis-change ``CircuitOp``.
dest_pauli_op: The destination Pauli type operator.
Returns:
The ``~CircuitOp @ StateFn`` composition equivalent to a state function defined by the
original ``PauliOp``.
"""
return ComposedOp([cob_instr_op.adjoint(), StateFn(dest_pauli_op)])
def operator_replacement_fn(
cob_instr_op: PrimitiveOp, dest_pauli_op: Union[PauliOp, PauliSumOp, ListOp]
) -> OperatorBase:
r"""
A built-in convenience replacement function which produces Operators
isomorphic to the origin ``PauliOp``.
Args:
cob_instr_op: The basis-change ``CircuitOp``.
dest_pauli_op: The destination ``PauliOp``.
Returns:
The ``~CircuitOp @ PauliOp @ CircuitOp`` composition isomorphic to the
original ``PauliOp``.
"""
return ComposedOp([cob_instr_op.adjoint(), dest_pauli_op, cob_instr_op])