Z2Symmetries
class Z2Symmetries(symmetries, sq_paulis, sq_list, tapering_values=None, tol=1e-14)
Bases: object
Z2 Symmetries
Parameters
- symmetries (
List[Pauli]) – the list of Pauli objects representing the Z_2 symmetries - sq_paulis (
List[Pauli]) – the list of single - qubit Pauli objects to construct the Clifford operators - sq_list (
List[int]) – the list of support of the single-qubit Pauli objects used to build the Clifford operators - tapering_values (
Optional[List[int]]) – values determines the sector. - tol (
float) – Tolerance threshold for ignoring real and complex parts of a coefficient.
Raises
OpflowError – Invalid paulis
Methods Defined Here
consistent_tapering
Z2Symmetries.consistent_tapering(operator)
Tapering the operator with the same manner of how this tapered operator is created. i.e., using the same Cliffords and tapering values.
Parameters
operator (PauliSumOp) – the to-be-tapered operator
Return type
OperatorBase
Returns
The tapered operator
Raises
OpflowError – The given operator does not commute with the symmetry
copy
Z2Symmetries.copy()
Get a copy of self. :rtype: Z2Symmetries :returns: copy
find_Z2_symmetries
classmethod Z2Symmetries.find_Z2_symmetries(operator)
Finds Z2 Pauli-type symmetries of an Operator.
Return type
Z2Symmetries
Returns
a z2_symmetries object contains symmetries, single-qubit X, single-qubit list.
is_empty
Z2Symmetries.is_empty()
Check the z2_symmetries is empty or not. :rtype: bool :returns: Empty or not
taper
Z2Symmetries.taper(operator)
Taper an operator based on the z2_symmetries info and sector defined by tapering_values. The tapering_values will be stored into the resulted operator for a record.
Parameters
operator (PauliSumOp) – the to-be-tapered operator.
Returns
[:class`PauliSumOp`]; otherwise, PauliSumOp
Return type
If tapering_values is None
Raises
OpflowError – Z2 symmetries, single qubit pauli and single qubit list cannot be empty
Attributes
cliffords
Get clifford operators, build based on symmetries and single-qubit X. :rtype: List[PauliSumOp] :returns: a list of unitaries used to diagonalize the Hamiltonian.
settings
Return operator settings.
Return type
Dict
sq_list
returns sq list
sq_paulis
returns sq paulis
symmetries
return symmetries
tapering_values
returns tapering values
tol
Tolerance threshold for ignoring real and complex parts of a coefficient.