def tensor(self,
other: OperatorBase) -> Union["CircuitStateFn", TensoredOp]:
r"""
Return tensor product between self and other, overloaded by ``^``.
Note: You must be conscious of Qiskit's big-endian bit printing convention.
Meaning, Plus.tensor(Zero)
produces a \|+⟩ on qubit 0 and a \|0⟩ on qubit 1, or \|+⟩⨂\|0⟩, but would produce
a QuantumCircuit like:
\|0⟩--
\|+⟩--
Because Terra prints circuits and results with qubit 0 at the end of the string or circuit.
Args:
other: The ``OperatorBase`` to tensor product with self.
Returns:
An ``OperatorBase`` equivalent to the tensor product of self and other.
"""
if isinstance(other, CircuitStateFn
) and other.is_measurement == self.is_measurement:
# Avoid reimplementing tensor, just use CircuitOp's
c_op_self = CircuitOp(self.primitive, self.coeff)
c_op_other = CircuitOp(other.primitive, other.coeff)
c_op = c_op_self.tensor(c_op_other)
if isinstance(c_op, CircuitOp):
return CircuitStateFn(
primitive=c_op.primitive, # pylint: disable=no-member
coeff=c_op.coeff,
is_measurement=self.is_measurement)
return TensoredOp([self, other])
def tensor(self, other: OperatorBase) -> OperatorBase:
if isinstance(other, VectorStateFn):
return StateFn(
self.primitive.tensor(other.primitive),
coeff=self.coeff * other.coeff,
is_measurement=self.is_measurement,
)
return TensoredOp([self, other])
def tensor(self, other: OperatorBase) -> Union["PauliSumOp", TensoredOp]:
if isinstance(other, PauliSumOp):
return PauliSumOp(
self.primitive.tensor(other.primitive),
coeff=self.coeff * other.coeff,
)
return TensoredOp([self, other])
def tensor(self, other: OperatorBase) -> OperatorBase:
# Both Paulis
if isinstance(other, PauliOp):
# Copying here because Terra's Pauli kron is in-place.
op_copy = Pauli((other.primitive.z, other.primitive.x))
return PauliOp(self.primitive.tensor(op_copy), coeff=self.coeff * other.coeff)
# pylint: disable=cyclic-import
from .circuit_op import CircuitOp
if isinstance(other, CircuitOp):
return self.to_circuit_op().tensor(other)
return TensoredOp([self, other])
def tensor(self, other: OperatorBase) -> OperatorBase:
# Both Paulis
if isinstance(other, PauliOp):
return PauliOp(self.primitive.tensor(other.primitive), coeff=self.coeff * other.coeff)
# pylint: disable=cyclic-import
from .pauli_sum_op import PauliSumOp
if isinstance(other, PauliSumOp):
new_primitive = SparsePauliOp(self.primitive).tensor(other.primitive)
return PauliSumOp(new_primitive, coeff=self.coeff * other.coeff)
from .circuit_op import CircuitOp
if isinstance(other, CircuitOp):
return self.to_circuit_op().tensor(other)
return TensoredOp([self, other])
def tensor(self, other: OperatorBase) -> Union["CircuitOp", TensoredOp]:
# pylint: disable=cyclic-import
from .pauli_op import PauliOp
from .matrix_op import MatrixOp
if isinstance(other, (PauliOp, CircuitOp, MatrixOp)):
other = other.to_circuit_op()
if isinstance(other, CircuitOp):
new_qc = QuantumCircuit(self.num_qubits + other.num_qubits)
# NOTE!!! REVERSING QISKIT ENDIANNESS HERE
new_qc.append(other.to_instruction(),
qargs=new_qc.qubits[0:other.primitive.num_qubits])
new_qc.append(self.to_instruction(),
qargs=new_qc.qubits[other.primitive.num_qubits:])
new_qc = new_qc.decompose()
return CircuitOp(new_qc, coeff=self.coeff * other.coeff)
return TensoredOp([self, other])
def tensor(self, other: OperatorBase) -> TensoredOp:
if isinstance(other, TensoredOp):
return TensoredOp([cast(OperatorBase, self)] + other.oplist)
return TensoredOp([self, other])
def tensor(self, other: OperatorBase) -> Union["MatrixOp", TensoredOp]:
if isinstance(other, MatrixOp):
return MatrixOp(self.primitive.tensor(other.primitive),
coeff=self.coeff * other.coeff)
return TensoredOp([self, other])
