org.mathIT.quantum

Class Circuit

java.lang.Object

java.util.AbstractCollection<E>

java.util.AbstractList<E>

java.util.ArrayList<QuantumGate>

org.mathIT.quantum.Circuit

All Implemented Interfaces:

Serializable, Cloneable, Iterable<QuantumGate>, Collection<QuantumGate>, List<QuantumGate>, RandomAccess

public class Circuit
extends ArrayList<QuantumGate>
implements Serializable

This class enables the storage of quantum circuits and offers methods to execute quantum operations on it. A quantum circuit consists of a sequence of quantum gates.

Version:

1.3

Author:

Andreas de Vries

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static String[]	gatelist In this array the names of all possible quantum gates are stored.

Fields inherited from class java.util.AbstractList

modCount

Constructor Summary

Constructors

Constructor and Description
Circuit() Creates an empty quantum circuit.

Method Summary

Modifier and Type	Method and Description
void	addCNOT(int[] qubits, boolean yRegister) Adds a CNOT gate on the two qubits specified by the two numbers in the qubit array; if the flag yRegister is set, it is added to the y-register, otherwise to the x-register.
void	addFunction(FunctionParser function) Adds a function evaluating gate to the circuit, specified by the input function.
void	addGrover(int needle) Adds the Grover gate searching for the specified needle to the circuit.
void	addHadamard(int i, boolean yRegister) Adds a Hadamard gate on the i-th qubit of the quantum circuit; if the flag yRegister is set, it is added to the i-th qubit of the y-register, otherwise it is the i-th qubit of the x-register.
void	addInvQFT(boolean yRegister) Adds the inverse Fourier transform gate to the circuit; if the flag yRegister is set, it is added to the y-register, otherwise to the x-register.
void	addInvSGate(int i, boolean yRegister) Adds an S* gate, the inverse or adjoint of the S gate, on the i-th qubit of the quantum circuit; if the flag yRegister is set, it is added to the i-th qubit of the y-register, otherwise it is the i-th qubit of the x-register.
void	addMeasurement(int[] qubits, boolean yRegister) Adds a measurement gate on the qubits specified by the qubit array; if the flag yRegister is set, it is added to the y-register, otherwise to the x-register.
void	addPauliX(int i, boolean yRegister) Adds a Pauli-X gate on the i-th qubit of the quantum circuit; if the flag yRegister is set, it is added to the i-th qubit of the y-register, otherwise it is the i-th qubit of the x-register.
void	addPauliY(int i, boolean yRegister) Adds a Pauli-Y gate on the i-th qubit of the quantum circuit; if the flag yRegister is set, it is added to the i-th qubit of the y-register, otherwise it is the i-th qubit of the x-register.
void	addPauliZ(int i, boolean yRegister) Adds a Pauli-Z gate on the i-th qubit of the quantum circuit; if the flag yRegister is set, it is added to the i-th qubit of the y-register, otherwise it is the i-th qubit of the x-register.
void	addQFT(boolean yRegister) Adds the Fourier transform gate to the circuit; if the flag yRegister is set, it is added to the y-register, otherwise to the x-register.
void	addRotation(int[] qubits, boolean yRegisterChosen, String axis, int phiAsPartOfPi) Adds a rotation gate to the circuit.
void	addSGate(int i, boolean yRegister) Adds an S gate on the i-th qubit of the quantum circuit; if the flag yRegister is set, it is added to the i-th qubit of the y-register, otherwise it is the i-th qubit of the x-register.
void	addSqrtX(int i, boolean yRegister) Adds a √X, or √NOT gate on the i-th qubit of the quantum circuit; if the flag yRegister is set, it is added to the i-th qubit of the y-register, otherwise it is the i-th qubit of the x-register.
void	addTGate(int i, boolean yRegister) Adds a T gate on the i-th qubit of the quantum circuit; if the flag yRegister is set, it is added to the i-th qubit of the y-register, otherwise it is the i-th qubit of the x-register.
void	addToffoli(int[] qubits, boolean yRegister) Adds a Toffoli gate on the three qubits specified by the three numbers in the qubit array; if the flag yRegister is set, it is added to the y-register, otherwise to the x-register.
boolean	executeAll() Executes the entire quantum circuit and returns true if the algorithm is terminated.
ArrayList<QuantumGate>	getGates() Provides the entire list of quantum gates of this quantum circuit.
QuantumGate	getNextGate() Yields the current gate in this quantum circuit which is to be executed next.
int	getNextGateNumber() Returns the number of the gate to be executed next in this quantum circuit.
int	getNumberOfWires() Returns the number of wires of this quantum circuit.
QuantumGate	getPreviousGate() Yields the previous gate in this quantum circuit which just had been executed.
Register	getXRegister() Returns the x-register of this quantum circuit.
int	getXRegisterSize() Yields the size of the x-register of this quantum circuit.
Register	getYRegister() Returns the y-register of this quantum circuit.
int	getYRegisterSize() Yields the size of the y-register of this quantum circuit.
void	initialize(int[] registerSizes, ArrayList<QuantumGate> gates) Constructs and initializes this quantum cicuit according to the specified sizes of the registers and the list of quantum gates.
boolean	initialize(int xRegisterSize, int yRegisterSize, int initialState) Initializes this quantum circuit and deletes all quantum gates.
void	initializeRegisters() Initializes this quantum register according to the initial qubit state given by quantum gate number 0.
void	setFinalStep() Sets the quantum cicuit into its final state.
void	setInitialQubits(int[] initialQubits) Sets the initial states of the qubits of this quantum circuit.
void	setInitialState(int[] initialQubits) Determines the initial state of the quantum circuit.
void	setNextStep() Executes the next quantum gate in this quantum circuit.
void	setPreviousStep() Executes the inverse of the previously executed quantum gate in this quantum circuit.

Methods inherited from class java.util.ArrayList

add, add, addAll, addAll, clear, clone, contains, ensureCapacity, forEach, get, indexOf, isEmpty, iterator, lastIndexOf, listIterator, listIterator, remove, remove, removeAll, removeIf, removeRange, replaceAll, retainAll, set, size, sort, spliterator, subList, toArray, toArray, trimToSize

Methods inherited from class java.util.AbstractList

equals, hashCode

Methods inherited from class java.util.AbstractCollection

containsAll, toString

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.List

containsAll, equals, hashCode

Methods inherited from interface java.util.Collection

parallelStream, stream

Field Detail

gatelist

public static String[] gatelist

In this array the names of all possible quantum gates are stored. These possible values are: "initialState", "Hadamard", "cNOT", "Pauli-X", "Pauli-Y", "Pauli-Z", "S", "T", "sqrt-X", "invS", "invT", "Toffoli", "QFT", "invQFT", "Function", "Rotation", "Grover", "Measurement" .

Constructor Detail

Circuit

public Circuit()

Creates an empty quantum circuit.

Method Detail

getXRegisterSize

public int getXRegisterSize()

Yields the size of the x-register of this quantum circuit.

Returns:

the size of the x-register

getYRegisterSize

public int getYRegisterSize()

Yields the size of the y-register of this quantum circuit.

Returns:

the size of the y-register

getNumberOfWires

public int getNumberOfWires()

Returns the number of wires of this quantum circuit.

Returns:

the number of quantum wires

setInitialQubits

public void setInitialQubits(int[] initialQubits)

Sets the initial states of the qubits of this quantum circuit.

Parameters:

initialQubits - the initial states of the qubits of this quantum circuit

getNextGate

public QuantumGate getNextGate()

Yields the current gate in this quantum circuit which is to be executed next.

Returns:

the next gate

getPreviousGate

public QuantumGate getPreviousGate()

Yields the previous gate in this quantum circuit which just had been executed.

Returns:

the previous gate

getNextGateNumber

public int getNextGateNumber()

Returns the number of the gate to be executed next in this quantum circuit. The initial state is counted as gate number 0.

Returns:

the next gate number

getXRegister

public Register getXRegister()

Returns the x-register of this quantum circuit.

Returns:

the x-register of this quantum circuit

getYRegister

public Register getYRegister()

Returns the y-register of this quantum circuit.

Returns:

the y-register of this quantum circuit

getGates

public ArrayList<QuantumGate> getGates()

Provides the entire list of quantum gates of this quantum circuit.

Returns:

the entire list of quantum gates of this circuit

initialize

public void initialize(int[] registerSizes,
                       ArrayList<QuantumGate> gates)

Constructs and initializes this quantum cicuit according to the specified sizes of the registers and the list of quantum gates. Any previously stored quantum gates of this circuit will be deleted.

Parameters:

registerSizes - the sizes of the registers, where registerSizes[0] denotes the size of the x-register, and registerSizes[1] denotes the size of the y-register

gates - the list of quantum gates this quantum gate consists of

initialize

public boolean initialize(int xRegisterSize,
                          int yRegisterSize,
                          int initialState)

Initializes this quantum circuit and deletes all quantum gates.

Parameters:

xRegisterSize - size of the x-register

yRegisterSize - size of the y-register

initialState - initial state of the register

Returns:

true if and only if initialization has been successful

initializeRegisters

public void initializeRegisters()

Initializes this quantum register according to the initial qubit state given by quantum gate number 0.

setFinalStep

public void setFinalStep()

Sets the quantum cicuit into its final state. In fact, by this method the entire quantum algorithm implemented by this circuit is executed.

setNextStep

public void setNextStep()

Executes the next quantum gate in this quantum circuit.

Throws:

IllegalArgumentException - if the quantum gate is unknown

setPreviousStep

public void setPreviousStep()

Executes the inverse of the previously executed quantum gate in this quantum circuit.

Throws:

IllegalArgumentException - if the quantum gate is unknown or if it is a measurement gate

setInitialState

public void setInitialState(int[] initialQubits)

Determines the initial state of the quantum circuit. Here the array initialQubits specifies the indices of qubits either set to |0> or |1>. That is, an initial state corresponds to a classical bit state.

Parameters:

initialQubits - the indices of qubits

addHadamard

public void addHadamard(int i,
                        boolean yRegister)
                 throws NoWireException

Adds a Hadamard gate on the i-th qubit of the quantum circuit; if the flag yRegister is set, it is added to the i-th qubit of the y-register, otherwise it is the i-th qubit of the x-register.

Parameters:

i - the number of qubit

yRegister - flag whether the gate is added in the y-register

Throws:

NoWireException - if the register is not existing

addCNOT

public void addCNOT(int[] qubits,
                    boolean yRegister)
             throws NoWireException

Adds a CNOT gate on the two qubits specified by the two numbers in the qubit array; if the flag yRegister is set, it is added to the y-register, otherwise to the x-register.

Parameters:

qubits - the numbers of qubit; array size must be two

yRegister - flag whether the gate is added in the y-register

Throws:

NoWireException - if the register is not existing

addPauliX

public void addPauliX(int i,
                      boolean yRegister)
               throws NoWireException

Adds a Pauli-X gate on the i-th qubit of the quantum circuit; if the flag yRegister is set, it is added to the i-th qubit of the y-register, otherwise it is the i-th qubit of the x-register.

Parameters:

i - the number of qubit

yRegister - flag whether the gate is added in the y-register

Throws:

NoWireException - if the register is not existing

addPauliY

public void addPauliY(int i,
                      boolean yRegister)
               throws NoWireException

Adds a Pauli-Y gate on the i-th qubit of the quantum circuit; if the flag yRegister is set, it is added to the i-th qubit of the y-register, otherwise it is the i-th qubit of the x-register.

Parameters:

i - the number of qubit

yRegister - flag whether the gate is added in the y-register

Throws:

NoWireException - if the register is not existing

addPauliZ

public void addPauliZ(int i,
                      boolean yRegister)
               throws NoWireException

Adds a Pauli-Z gate on the i-th qubit of the quantum circuit; if the flag yRegister is set, it is added to the i-th qubit of the y-register, otherwise it is the i-th qubit of the x-register.

Parameters:

i - the number of qubit

yRegister - flag whether the gate is added in the y-register

Throws:

NoWireException - if the register is not existing

addSGate

public void addSGate(int i,
                     boolean yRegister)
              throws NoWireException

Adds an S gate on the i-th qubit of the quantum circuit; if the flag yRegister is set, it is added to the i-th qubit of the y-register, otherwise it is the i-th qubit of the x-register.

Parameters:

i - the number of qubit

yRegister - flag whether the gate is added in the y-register

Throws:

NoWireException - if the register is not existing

addInvSGate

public void addInvSGate(int i,
                        boolean yRegister)
                 throws NoWireException

Adds an S^* gate, the inverse or adjoint of the S gate, on the i-th qubit of the quantum circuit; if the flag yRegister is set, it is added to the i-th qubit of the y-register, otherwise it is the i-th qubit of the x-register.

Parameters:

i - the number of qubit

yRegister - flag whether the gate is added in the y-register

Throws:

NoWireException - if the register is not existing

See Also:

addSGate(int, boolean)

addTGate

public void addTGate(int i,
                     boolean yRegister)
              throws NoWireException

Adds a T gate on the i-th qubit of the quantum circuit; if the flag yRegister is set, it is added to the i-th qubit of the y-register, otherwise it is the i-th qubit of the x-register.

Parameters:

i - the number of qubit

yRegister - flag whether the gate is added in the y-register

Throws:

NoWireException - if the register is not existing

addSqrtX

public void addSqrtX(int i,
                     boolean yRegister)
              throws NoWireException

Adds a √X, or √NOT gate on the i-th qubit of the quantum circuit; if the flag yRegister is set, it is added to the i-th qubit of the y-register, otherwise it is the i-th qubit of the x-register.

Parameters:

i - the number of qubit

yRegister - flag whether the gate is added in the y-register

Throws:

NoWireException - if the register is not existing

addToffoli

public void addToffoli(int[] qubits,
                       boolean yRegister)
                throws NoWireException

Adds a Toffoli gate on the three qubits specified by the three numbers in the qubit array; if the flag yRegister is set, it is added to the y-register, otherwise to the x-register.

Parameters:

qubits - the numbers of qubit; array size must be three

yRegister - flag whether the gate is added in the y-register

Throws:

NoWireException - if the register is not existing

addInvQFT

public void addInvQFT(boolean yRegister)
               throws NoWireException

Adds the inverse Fourier transform gate to the circuit; if the flag yRegister is set, it is added to the y-register, otherwise to the x-register.

Parameters:

yRegister - flag whether the gate is in the y-register

Throws:

NoWireException - if the number of wires vanishes

addQFT

public void addQFT(boolean yRegister)
            throws NoWireException

Adds the Fourier transform gate to the circuit; if the flag yRegister is set, it is added to the y-register, otherwise to the x-register.

Parameters:

yRegister - flag whether the gate is in the y-register

Throws:

NoWireException - if the number of wires vanishes

addFunction

public void addFunction(FunctionParser function)
                 throws NoWireException

Adds a function evaluating gate to the circuit, specified by the input function. The x-register qubits save as control qubits whereas the function values are strored in the y-register.

Parameters:

function - the parsed function

Throws:

NoWireException - if the numbers of wires is not positive

addRotation

public void addRotation(int[] qubits,
                        boolean yRegisterChosen,
                        String axis,
                        int phiAsPartOfPi)
                 throws NoWireException

Adds a rotation gate to the circuit. The axis may be x, y, or z, specified by the strings "x", "y", "z", respectively. The rotation angle is specified as the integer part of π.

Parameters:

qubits - the qubit numbers being involved

yRegisterChosen - flag whether the gate is added to the y-register

axis - the rotation axis

phiAsPartOfPi - the integer part of π representing the rotation angle

Throws:

NoWireException - if the number of wires vanishes

addGrover

public void addGrover(int needle)
               throws NoWireException

Adds the Grover gate searching for the specified needle to the circuit.

Parameters:

needle - the searched for value of the Grover gate

Throws:

NoWireException - if the number of wires vanishes

addMeasurement

public void addMeasurement(int[] qubits,
                           boolean yRegister)
                    throws NoWireException

Adds a measurement gate on the qubits specified by the qubit array; if the flag yRegister is set, it is added to the y-register, otherwise to the x-register.

Parameters:

qubits - the numbers of qubit

yRegister - flag whether the gate is added in the y-register

Throws:

NoWireException - if the register is not existing

executeAll

public boolean executeAll()

Executes the entire quantum circuit and returns true if the algorithm is terminated.

Returns:

true after termination of execution