Operations¶

`trueq.Operation`	Parent class of all primitive quantum operations.
`trueq.Block`	A blocking operation.
`trueq.Gate`	Represents a unitary quantum gate.
`trueq.Meas`	A measurement of a single qubit in the computational basis.
`trueq.NativeGate`	A subclass of `Gate` which introduces metadata attributes.
`trueq.Prep`	A preparation of a single qubit into the ground state of the computational basis.

Operation¶

class trueq.Operation¶: Parent class of all primitive quantum operations.

Block¶

class trueq.Block¶

A blocking operation.

This class holds no information, it allows a trueq.Circuit to keep track of where other operations are not allowed to be placed.

This is a singleton class; the constructor always yields the same instance.

Gate¶

class trueq.Gate(u)¶

Represents a unitary quantum gate.

import trueq as tq

tq.Gate([[0, 1], [1, 0]])

Many standard gates are predefined as attributes:

import trueq as tq

print("All available predefined gate names:")
print(list(tq.Gate.ALIASES))

# Accessing a predefined gate:
tq.Gate.cx

All available predefined gate names:
['id', 'x', 'y', 'z', 'cx', 'cy', 'cz', 'swap', 'iswap', 'h', 's', 't', 'ch', 'i', 'cnot', 'cliff0', 'cliff1', 'cliff2', 'cliff3', 'cliff4', 'cliff5', 'cliff6', 'cliff7', 'cliff8', 'cliff9', 'cliff10', 'cliff11', 'cliff12', 'cliff13', 'cliff14', 'cliff15', 'cliff16', 'cliff17', 'cliff18', 'cliff19', 'cliff20', 'cliff21', 'cliff22', 'cliff23']

The static method from_generators() can be used to construct gates from Pauli rotations.

Note

Gates are not checked to be unitary on instantiation; call is_unitary manually to check.

Parameters: u (numpy.ndarray-like | dict) – A unitary matrix in the computational basis.

ALIASES = {'ch': Gate.ch, 'cliff0': Gate.id, 'cliff1': Gate.x, 'cliff10': Gate.cliff10, 'cliff11': Gate.cliff11, 'cliff12': Gate.h, 'cliff13': Gate.cliff13, 'cliff14': Gate.cliff14, 'cliff15': Gate.cliff15, 'cliff16': Gate.cliff16, 'cliff17': Gate.cliff17, 'cliff18': Gate.cliff18, 'cliff19': Gate.cliff19, 'cliff2': Gate.y, 'cliff20': Gate.cliff20, 'cliff21': Gate.cliff21, 'cliff22': Gate.cliff22, 'cliff23': Gate.cliff23, 'cliff3': Gate.z, 'cliff4': Gate.cliff4, 'cliff5': Gate.cliff5, 'cliff6': Gate.cliff6, 'cliff7': Gate.cliff7, 'cliff8': Gate.cliff8, 'cliff9': Gate.s, 'cnot': Gate.cx, 'cx': Gate.cx, 'cy': Gate.cy, 'cz': Gate.cz, 'h': Gate.h, 'i': Gate.id, 'id': Gate.id, 'iswap': Gate.iswap, 's': Gate.s, 'swap': Gate.swap, 't': Gate.t, 'x': Gate.x, 'y': Gate.y, 'z': Gate.z}¶

A dictionary containing pre-defined gates where the keys are the gate names, for example CNOT, or H. Gates in this dictionary can be accessed using trueq.Gate.<gate_name>, for example:

import trueq as tq
tq.Gate.cx

static from_generators(*args)¶

Constructs a Gate instance from rotations about Paulis. Specifically, the gate is constructed as \(exp(-1j * \sum_i (\pi\theta_i/180) P_i/ 2)\) where \(P_i\) are the input Pauli strings and \(\theta_i\) are the input rotation angles in degrees. This can be input either as an alternating sequence of Pauli strings and angles, or as a dict.

import trueq as tq

g1 = tq.Gate.from_generators("X", 90)
g2 = tq.Gate.from_generators("XX", 90, "YY", 180)
g3 = tq.Gate.from_generators({"XX": 90, "YY": 180})

g2

Parameters: args – A dictionary mapping Pauli strings to angles in degrees, or an alternating sequence thereof.
Return type: Gate

property is_unitary¶

Whether or not this gate is unitary to numerical precision.

Type: bool

property is_identity¶

Whether or not this gate is the identity gate to numerical precision.

Type: bool

property mat¶

The matrix representation of this gate in the canonical basis.

Type: numpy.ndarray

property width¶

The number of columns of the matrix representation of this gate.

Type: int

property expansion¶

Assuming this gate acts on qubits, a sparse representation of this gate in terms of the trueq.math.frame.pauli_basis; a dictionary mapping Pauli strings to (complex) coefficients.

Type: dict

static from_alias(alias)¶

Returns a Gate from common names, such as CX, swap, H, S etc.

ALIASES is a dictionary which stores available gates.

Raises: KeyError – If the gate is not found.

property generators¶

Assumes this gate acts on qubits and returns rotations about Pauli axes performed by this Gate. Specifically, outputs a description of this gate in the form: \(exp(-1j * \sum_i (\pi\theta_i/180) P_i/ 2)\) where \(P_i\) are the Pauli strings and \(\theta_i\) are the rotation angles in degrees.

import trueq as tq

tq.Gate.from_generators("X", 90, "Z", 20).generators
{"X": 90, "Z": 20}

{'X': 90, 'Z': 20}

Type: dict

property adj¶

A new Gate instance which is the conjugate transpose of this gate.

Type: Gate

static random(dim)¶

Generate a Haar random unitary gate of dimension dim.

Parameters: dim (int) – The dimension of the gate.
Return type: Gate

plot(abs_max=None, ax=None)¶

Plots the matrix representation of this gate.

Parameters

abs_max (None | float) – The value to scale absolute values of the matrix by; the value at which plotted colors become fully opaque. By default, this is the largest absolute magnitude of the input matrix.
ax (matplotlib.Axis) – An existing axis to plot on. If not given, a new figure will be created.

Measurement¶

class trueq.Meas¶

A measurement of a single qubit in the computational basis.

This class holds no information, it allows a trueq.Circuit to keep track of where a measurement has taken place.

This is a singleton class; the constructor always yields the same instance.

Native Gate¶

class trueq.NativeGate(name, u, params=None, classname=None)¶

A subclass of Gate which introduces metadata attributes.

name is a string giving a name to the gate.

(optional) parameters is a dictionary that maps parameter names to parameter values.

(optional) classname is a string specifying the factory that constructed this instance.

These attributes are entirely metadata; there are no automatic consistency checks between them and the matrix representation. The purpose of these attributes is to provide tools, such as transpilers to third-party circuit formats, with a fast method of identifying gates without introspecting matrices. This requires trust that these metadata were generated correctly and in good faith.

Native gates are typically (and most easily) constructed by GateFactorys, which are usually owned by Config objects.

import trueq as tq

config = tq.Config.basic("example")
config.X(90)

Native gates are not intended to be mutable, and the parameters and names should not be changed after instantiation.

Parameters

name (str) – Name of the gate operation.
u (dict) – See Gate.
params (dict) – Any parameters that the gate needs in order to be constructed.
classname – The constructing class name of this native gate. This is usually assigned by a GateFactory on instantiation.

static from_generators(name, *args, params=None, classname=None)¶

Constructs a NativeGate instance from rotations about Paulis. Also adds a name and any parameters used to construct the native gate. Specifically, the output gate in this case is given by \(exp(-1j * \sum_i (\pi\theta_i/180) P_i/ 2)\) where \(P_i\) are the input Pauli strings and \(\theta_i\) are the input rotation angles in degrees. This can be input either as an alternating sequence of Pauli strings and angles, or as a dict.

import trueq as tq

g1 = tq.NativeGate.from_generators("name", "X", 90, params={"theta": 90})
g2 = tq.NativeGate.from_generators("name", "XX", 90, "YY", 180)
g3 = tq.NativeGate.from_generators("name", {"XX": 90, "YY": 180})

g1

Parameters

name (str) – Name of the gate operation.
params (dict) – Any parameters that the gate needs in order to be constructed.
args – A dictionary mapping Pauli strings to angles in degrees, or an alternating sequence thereof.
classname (str) – The constructing class name of this native gate. This is usually assigned by a GateFactory on instantiation.

Return type

NativeGate

property parameters¶

The stored parameters.

Type: dict

property name¶

The name of this native gate.

Type: str

property classname¶

The constructing class name of this native gate. This is usually assigned by a GateFactory on instantiation.

Type: str

Preparation¶

class trueq.Prep¶

A preparation of a single qubit into the ground state of the computational basis.

This class holds no information, it allows a trueq.Circuit to keep track of where a state preparation has taken place.

This is a singleton class; the constructor always yields the same instance.