cirq.Pauli

Represents the Pauli gates.

Inherits From: Gate

cirq.Pauli(
    index: int, name: str
) -> None

This is an abstract class with no public subclasses. The only instances of private subclasses are the X, Y, or Z Pauli gates defined below.

Methods

`by_index`

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@staticmethod
by_index(
    index: int
) -> 'Pauli'

`by_relative_index`

View source

@staticmethod
by_relative_index(
    p: 'Pauli', relative_index: int
) -> 'Pauli'

`controlled`

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controlled(
    num_controls: Optional[int] = None,
    control_values: Optional[Union[cv.AbstractControlValues, Sequence[Union[int, Collection[int]]]]
        ] = None,
    control_qid_shape: Optional[Tuple[int, ...]] = None
) -> 'Gate'

Returns a controlled version of this gate. If no arguments are specified, defaults to a single qubit control.

Args
`num_controls`	Total number of control qubits.
`control_values`	Which control computational basis state to apply the sub gate. A sequence of length `num_controls` where each entry is an integer (or set of integers) corresponding to the computational basis state (or set of possible values) where that control is enabled. When all controls are enabled, the sub gate is applied. If unspecified, control values default to 1.
`control_qid_shape`	The qid shape of the controls. A tuple of the expected dimension of each control qid. Defaults to `(2,) * num_controls`. Specify this argument when using qudits.

Returns
A `cirq.Gate` representing `self` controlled by the given control values and qubits. This is a `cirq.ControlledGate` in the base implementation, but subclasses may return a different gate type.

`num_qubits`

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num_qubits()

The number of qubits this gate acts on.

`on`

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on(
    *qubits
) -> 'SingleQubitPauliStringGateOperation'

Returns an application of this gate to the given qubits.

Args
`*qubits`	The collection of qubits to potentially apply the gate to.

Raises
`ValueError`	If more than one qubit is acted upon.

`on_each`

View source

on_each(
    *targets
) -> List['cirq.Operation']

Returns a list of operations applying the gate to all targets.

Args
`*targets`	The qubits to apply this gate to. For single-qubit gates this can be provided as varargs or a combination of nested iterables. For multi-qubit gates this must be provided as an `Iterable[Sequence[Qid]]`, where each sequence has `num_qubits` qubits.

Returns
Operations applying this gate to the target qubits.

Raises
`ValueError`	If targets are not instances of Qid or Iterable[Qid]. If the gate qubit number is incompatible.
`TypeError`	If a single target is supplied and it is not iterable.

`phased_pauli_product`

View source

phased_pauli_product(
    other: Union['cirq.Pauli', 'identity.IdentityGate']
) -> Tuple[complex, Union['cirq.Pauli', 'identity.IdentityGate']]

`relative_index`

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relative_index(
    second: 'Pauli'
) -> int

Relative index of self w.r.t. second in the (X, Y, Z) cycle.

`third`

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third(
    second: 'Pauli'
) -> 'Pauli'

`validate_args`

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validate_args(
    qubits: Sequence['cirq.Qid']
) -> None

Checks if this gate can be applied to the given qubits.

By default checks that:

inputs are of type Qid
len(qubits) == num_qubits()
qubit_i.dimension == qid_shape[i] for all qubits

Child classes can override. The child implementation should call super().validate_args(qubits) then do custom checks.

Args
`qubits`	The sequence of qubits to potentially apply the gate to.

Raises
`ValueError`	The gate can't be applied to the qubits.

`with_probability`

View source

with_probability(
    probability: 'cirq.TParamVal'
) -> 'cirq.Gate'

Creates a probabilistic channel with this gate.

Args
`probability`	floating point value between 0 and 1, giving the probability this gate is applied.

Returns
`cirq.RandomGateChannel` that applies `self` with probability `probability` and the identity with probability `1-p`.

`wrap_in_linear_combination`

View source

wrap_in_linear_combination(
    coefficient: 'cirq.TParamValComplex' = 1
) -> 'cirq.LinearCombinationOfGates'

Returns a LinearCombinationOfGates with this gate.

Args
`coefficient`	number coefficient to use in the resulting `cirq.LinearCombinationOfGates` object.

Returns
`cirq.LinearCombinationOfGates` containing self with a coefficient of `coefficient`.

`add`

View source

__add__(
    other: Union['Gate', 'cirq.LinearCombinationOfGates']
) -> 'cirq.LinearCombinationOfGates'

`call`

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__call__(
    *qubits, **kwargs
)

Call self as a function.

`gt`

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__gt__(
    other
)

Return self>value.

`lt`

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__lt__(
    other
)

Return self<value.

`mul`

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__mul__(
    other: complex
) -> 'cirq.LinearCombinationOfGates'

`neg`

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__neg__() -> 'cirq.LinearCombinationOfGates'

`pow`

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__pow__(
    power
)

`rmul`

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__rmul__(
    other: complex
) -> 'cirq.LinearCombinationOfGates'

`sub`

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__sub__(
    other: Union['Gate', 'cirq.LinearCombinationOfGates']
) -> 'cirq.LinearCombinationOfGates'

`truediv`

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__truediv__(
    other: complex
) -> 'cirq.LinearCombinationOfGates'