cirq.SupportsCommutes

An object that can determine commutation relationships vs others.

cirq.SupportsCommutes(
    *args, **kwargs
)

Methods

`_commutes_`

View source

_commutes_(
    other: Any, *, atol: float
) -> Union[None, bool, NotImplementedType]

Determines if this object commutes with the other object.

Can return None to indicate the commutation relationship is indeterminate (e.g. incompatible matrix sizes). Can return NotImplemented to indicate to the caller that they should try some other way of determining the commutation relationship.

Args

other The other object that may or may not commute with the receiving object.

atol Absolute error tolerance. Some objects that commute may appear to not quite commute, due to rounding error from floating point computations. This parameter indicates an acceptable level of deviation from exact commutativity. The exact meaning of what error is being tolerated is not specified. It could be the maximum angle between rotation axes in the Bloch sphere, or the maximum trace of the absolute value of the commutator, or some other value convenient to the implementor of the method.

Args
`other`	The other object that may or may not commute with the receiving object.
`atol`	Absolute error tolerance. Some objects that commute may appear to not quite commute, due to rounding error from floating point computations. This parameter indicates an acceptable level of deviation from exact commutativity. The exact meaning of what error is being tolerated is not specified. It could be the maximum angle between rotation axes in the Bloch sphere, or the maximum trace of the absolute value of the commutator, or some other value convenient to the implementor of the method.

Returns
Whether or not the values commute.
`True`	`self` commutes with `other` within absolute tolerance `atol`.
`False`	`self` does not commute with `other`.
`None`	There is not a well defined commutation result. For example, whether or not parameterized operations will commute may depend on the parameter values and so is indeterminate.
`NotImplemented`	Unable to determine anything about commutativity. Consider falling back to other strategies, such as asking `other` if it commutes with `self` or computing the unitary matrices of both values.