cirq.QubitOrder

Defines the kronecker product order of qubits.

cirq.QubitOrder(
    explicit_func: Callable[[Iterable[cirq.Qid]], tuple[cirq.Qid, ...]]
) -> None

Used in the tutorials
Routing with t\|ket>

Methods

@staticmethod
as_qubit_order(
    val: cirq.QubitOrderOrList
) -> QubitOrder

Converts a value into a basis.

Args
`val`	An iterable or a basis.

Returns
The basis implied by the value.

Raises
`ValueError`	If `val` is not an iterable or a `QubitOrder`.

@staticmethod
explicit(
    fixed_qubits: Iterable[cirq.Qid], fallback: (QubitOrder | None) = None
) -> QubitOrder

A basis that contains exactly the given qubits in the given order.

Args
`fixed_qubits`	The qubits in basis order.
`fallback`	A fallback order to use for extra qubits not in the fixed_qubits list. Extra qubits will always come after the fixed_qubits, but will be ordered based on the fallback. If no fallback is specified, a ValueError is raised when extra qubits are specified.

Returns
A Basis instance that forces the given qubits in the given order.

Raises
`ValueError`	If a qubit appears twice in `fixed_qubits`, or there were is no fallback specified but there are extra qubits.

map(
    internalize: Callable[[TExternalQubit], TInternalQubit],
    externalize: Callable[[TInternalQubit], TExternalQubit]
) -> QubitOrder

Transforms the Basis so that it applies to wrapped qubits.

Args
`externalize`	Converts an internal qubit understood by the underlying basis into an external qubit understood by the caller.
`internalize`	Converts an external qubit understood by the caller into an internal qubit understood by the underlying basis.

Returns
A basis that transforms qubits understood by the caller into qubits understood by an underlying basis, uses that to order the qubits, then wraps the ordered qubits back up for the caller.

order_for(
    qubits: Iterable[cirq.Qid]
) -> tuple[cirq.Qid, ...]

Returns a qubit tuple ordered corresponding to the basis.

Args
`qubits`	Qubits that should be included in the basis. (Additional qubits may be added into the output by the basis.)

Returns
A tuple of qubits in the same order that their single-qubit matrices would be passed into `np.kron` when producing a matrix for the entire system.

@staticmethod
sorted_by(
    key: Callable[[cirq.Qid], Any]
) -> QubitOrder

A basis that orders qubits ascending based on a key function.

Args
`key`	A function that takes a qubit and returns a key value. The basis will be ordered ascending according to these key values.

Returns
A basis that orders qubits ascending based on a key function.

Class Variables
DEFAULT	Instance of `cirq.QubitOrder`