qml.labs.resource_estimation.ResourceGlobalPhase

class ResourceGlobalPhase(*args, wires=None, **kwargs)[source]

Bases: ResourceOperator

Resource class for the GlobalPhase gate.

Parameters:

wires (Iterable[Any], optional) – the wires the operator acts on

Resources:

The GlobalPhase gate is treated as a free gate and thus it cannot be decomposed further. Requesting the resources of this gate returns an empty list.

See also

GlobalPhase

Example

The resources for this operation are computed using:

>>> plre.ResourceGlobalPhase.resource_decomp()
[]

num_wires

resource_keys

resource_params

Returns a dictionary containing the minimal information needed to compute the resources.

num_wires = 0
resource_keys = {}
resource_params

Returns a dictionary containing the minimal information needed to compute the resources.

Returns:

Empty dictionary. The resources of this operation don’t depend on any additional parameters.

Return type:

dict

adjoint_resource_decomp(*args, **kwargs)

Returns a list of actions that define the resources of the operator.

controlled_resource_decomp(...)

Returns a list representing the resources for a controlled version of the operator.

default_adjoint_resource_decomp()

Returns a list representing the resources for the adjoint of the operator.

default_controlled_resource_decomp(...)

Returns a list representing the resources for a controlled version of the operator.

default_pow_resource_decomp(pow_z)

Returns a list representing the resources for an operator raised to a power.

default_resource_decomp(**kwargs)

Returns a list representing the resources of the operator.

dequeue(op_to_remove[, context])

Remove the given resource operator(s) from the Operator queue.

pow_resource_decomp(pow_z, *args, **kwargs)

Returns a list representing the resources for an operator raised to a power.

queue([context])

Append the operator to the Operator queue.

resource_decomp(*args, **kwargs)

Returns a list of actions that define the resources of the operator.

resource_rep(**kwargs)

Returns a compressed representation containing only the parameters of the Operator that are needed to compute the resources.

resource_rep_from_op()

Returns a compressed representation directly from the operator

set_resources(new_func[, override_type])

Set a custom function to override the default resource decomposition.

tracking_name(*args, **kwargs)

Returns a name used to track the operator during resource estimation.

tracking_name_from_op()

Returns the tracking name built with the operator's parameters.

classmethod adjoint_resource_decomp(*args, **kwargs)

Returns a list of actions that define the resources of the operator.

classmethod controlled_resource_decomp(ctrl_num_ctrl_wires, ctrl_num_ctrl_values, *args, **kwargs)

Returns a list representing the resources for a controlled version of the operator.

Parameters:
  • ctrl_num_ctrl_wires (int) – the number of qubits the operation is controlled on

  • ctrl_num_ctrl_values (int) – the number of control qubits, that are controlled when in the \(|0\rangle\) state

classmethod default_adjoint_resource_decomp()[source]

Returns a list representing the resources for the adjoint of the operator.

Resources:

The adjoint of a global phase operator changes the sign of the phase, thus the resources of the adjoint operation is the original operation.

Returns:

A list of GateCount objects, where each object represents a specific quantum gate and the number of times it appears in the decomposition.

Return type:

list[GateCount]

classmethod default_controlled_resource_decomp(ctrl_num_ctrl_wires, ctrl_num_ctrl_values)[source]

Returns a list representing the resources for a controlled version of the operator.

Parameters:
  • ctrl_num_ctrl_wires (int) – the number of qubits the operation is controlled on

  • ctrl_num_ctrl_values (int) – The number of control qubits, that are controlled when in the \(|0\rangle\) state.

Resources:

The resources are generated from the fact that a global phase controlled on a single qubit is equivalent to a local phase shift on that control qubit. This idea can be generalized to a multi-qubit global phase by introducing one ‘clean’ auxilliary qubit which gets reset at the end of the computation. In this case, we sandwich the phase shift operation with two multi-controlled X gates.

Returns:

A list of GateCount objects, where each object represents a specific quantum gate and the number of times it appears in the decomposition.

Return type:

list[GateCount]

classmethod default_pow_resource_decomp(pow_z)[source]

Returns a list representing the resources for an operator raised to a power.

Parameters:

pow_z (int) – the power that the operator is being raised to

Resources:

Taking arbitrary powers of a global phase produces a sum of global phases. The resources simplify to just one total global phase operator.

Returns:

A list of GateCount objects, where each object represents a specific quantum gate and the number of times it appears in the decomposition.

Return type:

list[GateCount]

classmethod default_resource_decomp(**kwargs)[source]

Returns a list representing the resources of the operator. Each object represents a quantum gate and the number of times it occurs in the decomposition.

Resources:

The GlobalPhase gate is treated as a free gate and thus it cannot be decomposed further. Requesting the resources of this gate returns an empty list.

Returns:

empty list

Return type:

list

static dequeue(op_to_remove, context=<class 'pennylane.queuing.QueuingManager'>)

Remove the given resource operator(s) from the Operator queue.

classmethod pow_resource_decomp(pow_z, *args, **kwargs)

Returns a list representing the resources for an operator raised to a power.

Parameters:

pow_z (int) – exponent that the operator is being raised to

queue(context=<class 'pennylane.queuing.QueuingManager'>)

Append the operator to the Operator queue.

classmethod resource_decomp(*args, **kwargs)

Returns a list of actions that define the resources of the operator.

classmethod resource_rep(**kwargs)[source]

Returns a compressed representation containing only the parameters of the Operator that are needed to compute the resources.

resource_rep_from_op()

Returns a compressed representation directly from the operator

classmethod set_resources(new_func, override_type='base')

Set a custom function to override the default resource decomposition.

This method allows users to replace any of the resource_decomp, adjoint_resource_decomp, ctrl_resource_decomp, or pow_resource_decomp methods globally for every instance of the class.

classmethod tracking_name(*args, **kwargs)

Returns a name used to track the operator during resource estimation.

tracking_name_from_op()

Returns the tracking name built with the operator’s parameters.