import {ComputeEngine} from 'projectq/src/meta/compute.js'

public class | source

ComputeEngine

Extends:

BasicEngine → ComputeEngine

Adds Compute-tags to all commands and stores them (to later uncompute them automatically)

Constructor Summary

Public Constructor
public	constructor()

Member Summary

Public Members
public	allocatedQubitIDs: *
public	deallocatedQubitIDs: *

Private Members
private	_compute: boolean
private	_l: *[]

Method Summary

Public Methods
public	addUnComputeTag(cmd: Command): * Modify the command tags, inserting an UncomputeTag.
public	endCompute() End the compute step (exit the Compute() - statement).
public	receive(commandList: Command[]) If in compute-mode: Receive commands and store deepcopy of each cmd.
public	runUnCompute() Send uncomputing gates.

Inherited Summary

From class BasicEngine
public	isLastEngine: boolean
public	allocateQubit(dirty: boolean): Qureg Return a new qubit as a list containing 1 qubit object (quantum register of size 1).
public	allocateQureg(n: number): Qureg Allocate n qubits and return them as a quantum register, which is a list of qubit objects.
public	deallocateQubit(qubit: BasicQubit) Deallocate a qubit (and sends the deallocation command down the pipeline).
public	isAvailable(cmd: Command): boolean Default implementation of isAvailable: Ask the next engine whether a command is available, i.e., whether it can be executed by the next engine(s).
public	isMetaTagSupported(metaTag: function): boolean Check if there is a compiler engine handling the meta tag
public	receive()
public	send(commandList: Command[]) Forward the list of commands to the next engine in the pipeline.

Public Constructors

public constructor() source

Override:

BasicEngine#constructor

Public Members

public allocatedQubitIDs: * source

public deallocatedQubitIDs: * source

Private Members

private _compute: boolean source

private _l: *[] source

Public Methods

public addUnComputeTag(cmd: Command): * source

Modify the command tags, inserting an UncomputeTag.

Params:

Name	Type	Attribute	Description
cmd	Command		Command to modify.

Return:

public endCompute() source

End the compute step (exit the Compute() - statement).

Will tell the Compute-engine to stop caching. It then waits for the uncompute instruction, which is when it sends all cached commands inverted and in reverse order down to the next compiler engine.

Throw:

QubitManagementError

If qubit has been deallocated in Compute section which has not been allocated in Compute section

public receive(commandList: Command[]) source

If in compute-mode: Receive commands and store deepcopy of each cmd. Add ComputeTag to received cmd and send it on. Otherwise: send all received commands directly to next_engine.

Override:

BasicEngine#receive

Params:

Name	Type	Attribute	Description
commandList	Command[]		List of commands to receive.

public runUnCompute() source

Send uncomputing gates.

Sends the inverse of the stored commands in reverse order down to the next engine. And also deals with allocated qubits in Compute section. If a qubit has been allocated during compute, it will be deallocated during uncompute. If a qubit has been allocated and deallocated during compute, then a new qubit is allocated and deallocated during uncompute.