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bsr

BlochSphereRotation

Bases: GateSemantic, IRNode

Source code in opensquirrel/ir/semantics/bsr.py 
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class BlochSphereRotation(GateSemantic, IRNode):
    normalize_angle_params: bool = True

    def __init__(
        self,
        axis: AxisLike,
        angle: SupportsFloat,
        phase: SupportsFloat,
    ) -> None:
        self.axis = Axis(axis)
        self.angle = normalize_angle(angle) if self.normalize_angle_params else float(angle)
        self.phase = normalize_angle(phase) if self.normalize_angle_params else float(phase)

    def accept(self, visitor: IRVisitor) -> Any:
        """Accepts visitor and processes this IR node."""
        return visitor.visit_bloch_sphere_rotation(self)

    def is_identity(self) -> bool:
        """Checks if the Bloch sphere rotation represents an identity operation.

        Returns:
            True if the Bloch sphere rotation represents an identity operation, False otherwise.

        """
        return abs(self.angle) < ATOL and abs(self.phase) < ATOL

    def __eq__(self, other: object) -> bool:
        if not isinstance(other, BlochSphereRotation):
            return False

        if np.allclose(self.axis.value, other.axis.value, atol=ATOL):
            return abs(self.angle - other.angle) < ATOL and abs(self.phase - other.phase) < ATOL

        if np.allclose(self.axis.value, -other.axis.value, atol=ATOL):
            return abs(self.angle + other.angle) < ATOL and abs(self.phase + other.phase) < ATOL

        return False

    def __mul__(self, other: BlochSphereRotation) -> BlochSphereRotation:
        """Computes the Bloch sphere rotation resulting from the multiplication of two Bloch sphere
        rotations. Note that the multiplication of Bloch sphere rotations `A * B` corrensponds to
        linear operation $B \\cdot A$.

        Notes:
            - It is checked whether the result is a known gate.
            - Uses [Rodrigues' rotation formula](https://en.wikipedia.org/wiki/Rodrigues%27_rotation_formula).

        Args:
            other (BlochSphereRotation): The second Bloch sphere rotation to multiply with.

        Returns:
            The resulting Bloch sphere rotation.

        """
        acos_argument = cos(self.angle / 2) * cos(other.angle / 2) - sin(self.angle / 2) * sin(
            other.angle / 2
        ) * np.dot(self.axis, other.axis)
        combined_angle = 2 * acos(acos_argument)

        if abs(sin(combined_angle / 2)) < ATOL:
            return bsr_from_matrix([[1, 0], [0, 1]])

        order_of_magnitude = abs(floor(log10(ATOL)))
        combined_axis = np.round(
            (
                1
                / sin(combined_angle / 2)
                * (
                    sin(self.angle / 2) * cos(other.angle / 2) * self.axis.value
                    + cos(self.angle / 2) * sin(other.angle / 2) * other.axis.value
                    + sin(self.angle / 2) * sin(other.angle / 2) * np.cross(other.axis, self.axis)
                )
            ),
            order_of_magnitude,
        )

        combined_phase = np.round(self.phase + other.phase, order_of_magnitude)
        return BlochSphereRotation(
            axis=combined_axis,
            angle=combined_angle,
            phase=combined_phase,
        )

    def __repr__(self) -> str:
        return (
            f"BlochSphereRotation(axis={repr_round(self.axis)}, angle={repr_round(self.angle)}, "
            f"phase={repr_round(self.phase)})"
        )

__mul__ 

__mul__(other: BlochSphereRotation) -> BlochSphereRotation

Computes the Bloch sphere rotation resulting from the multiplication of two Bloch sphere rotations. Note that the multiplication of Bloch sphere rotations A * B corrensponds to linear operation \(B \cdot A\).

Notes

Parameters:

Name Type Description Default
other BlochSphereRotation

The second Bloch sphere rotation to multiply with.

 required

Returns:

Type Description
BlochSphereRotation

The resulting Bloch sphere rotation.
Source code in opensquirrel/ir/semantics/bsr.py 
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def __mul__(self, other: BlochSphereRotation) -> BlochSphereRotation:
    """Computes the Bloch sphere rotation resulting from the multiplication of two Bloch sphere
    rotations. Note that the multiplication of Bloch sphere rotations `A * B` corrensponds to
    linear operation $B \\cdot A$.

    Notes:
        - It is checked whether the result is a known gate.
        - Uses [Rodrigues' rotation formula](https://en.wikipedia.org/wiki/Rodrigues%27_rotation_formula).

    Args:
        other (BlochSphereRotation): The second Bloch sphere rotation to multiply with.

    Returns:
        The resulting Bloch sphere rotation.

    """
    acos_argument = cos(self.angle / 2) * cos(other.angle / 2) - sin(self.angle / 2) * sin(
        other.angle / 2
    ) * np.dot(self.axis, other.axis)
    combined_angle = 2 * acos(acos_argument)

    if abs(sin(combined_angle / 2)) < ATOL:
        return bsr_from_matrix([[1, 0], [0, 1]])

    order_of_magnitude = abs(floor(log10(ATOL)))
    combined_axis = np.round(
        (
            1
            / sin(combined_angle / 2)
            * (
                sin(self.angle / 2) * cos(other.angle / 2) * self.axis.value
                + cos(self.angle / 2) * sin(other.angle / 2) * other.axis.value
                + sin(self.angle / 2) * sin(other.angle / 2) * np.cross(other.axis, self.axis)
            )
        ),
        order_of_magnitude,
    )

    combined_phase = np.round(self.phase + other.phase, order_of_magnitude)
    return BlochSphereRotation(
        axis=combined_axis,
        angle=combined_angle,
        phase=combined_phase,
    )

accept 

accept(visitor: IRVisitor) -> Any

Accepts visitor and processes this IR node.

Source code in opensquirrel/ir/semantics/bsr.py 
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def accept(self, visitor: IRVisitor) -> Any:
    """Accepts visitor and processes this IR node."""
    return visitor.visit_bloch_sphere_rotation(self)

is_identity 

is_identity() -> bool

Checks if the Bloch sphere rotation represents an identity operation.

Returns:

Type Description
bool

True if the Bloch sphere rotation represents an identity operation, False otherwise.
Source code in opensquirrel/ir/semantics/bsr.py 
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def is_identity(self) -> bool:
    """Checks if the Bloch sphere rotation represents an identity operation.

    Returns:
        True if the Bloch sphere rotation represents an identity operation, False otherwise.

    """
    return abs(self.angle) < ATOL and abs(self.phase) < ATOL

BsrAngleParam

Bases: BlochSphereRotation

Source code in opensquirrel/ir/semantics/bsr.py 
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class BsrAngleParam(BlochSphereRotation):
    def __init__(
        self,
        axis: AxisLike,
        angle: SupportsFloat,
        phase: SupportsFloat,
    ) -> None:
        BlochSphereRotation.__init__(self, axis, angle, phase)
        self.theta = Float(self.angle)

    @property
    def arguments(self) -> tuple[Float, ...]:
        return (self.theta,)

    def accept(self, visitor: IRVisitor) -> Any:
        """Accepts visitor and processes this IR node."""
        visit_bsr = super().accept(visitor)
        return visit_bsr if visit_bsr is not None else visitor.visit_bsr_angle_param(self)

accept 

accept(visitor: IRVisitor) -> Any

Accepts visitor and processes this IR node.

Source code in opensquirrel/ir/semantics/bsr.py 
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def accept(self, visitor: IRVisitor) -> Any:
    """Accepts visitor and processes this IR node."""
    visit_bsr = super().accept(visitor)
    return visit_bsr if visit_bsr is not None else visitor.visit_bsr_angle_param(self)

BsrFullParams

Bases: BlochSphereRotation

Source code in opensquirrel/ir/semantics/bsr.py 
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class BsrFullParams(BlochSphereRotation):
    def __init__(self, axis: AxisLike, angle: SupportsFloat, phase: SupportsFloat) -> None:
        BlochSphereRotation.__init__(self, axis, angle, phase)
        self.nx, self.ny, self.nz = (Float(component) for component in Axis(axis))
        self.theta = Float(self.angle)
        self.phi = Float(self.phase)

    @property
    def arguments(self) -> tuple[Float, ...]:
        return self.nx, self.ny, self.nz, self.theta, self.phi

    def accept(self, visitor: IRVisitor) -> Any:
        """Accepts visitor and processes this IR node."""
        visit_bsr = super().accept(visitor)
        return visit_bsr if visit_bsr is not None else visitor.visit_bsr_full_params(self)

accept 

accept(visitor: IRVisitor) -> Any

Accepts visitor and processes this IR node.

Source code in opensquirrel/ir/semantics/bsr.py 
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def accept(self, visitor: IRVisitor) -> Any:
    """Accepts visitor and processes this IR node."""
    visit_bsr = super().accept(visitor)
    return visit_bsr if visit_bsr is not None else visitor.visit_bsr_full_params(self)

BsrNoParams

Bases: BlochSphereRotation

Source code in opensquirrel/ir/semantics/bsr.py 
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class BsrNoParams(BlochSphereRotation):
    def __init__(
        self,
        axis: AxisLike,
        angle: SupportsFloat,
        phase: SupportsFloat,
    ) -> None:
        BlochSphereRotation.__init__(self, axis, angle, phase)

    def accept(self, visitor: IRVisitor) -> Any:
        """Accepts visitor and processes this IR node."""
        visit_bsr = super().accept(visitor)
        return visit_bsr if visit_bsr is not None else visitor.visit_bsr_no_params(self)

accept 

accept(visitor: IRVisitor) -> Any

Accepts visitor and processes this IR node.

Source code in opensquirrel/ir/semantics/bsr.py 
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def accept(self, visitor: IRVisitor) -> Any:
    """Accepts visitor and processes this IR node."""
    visit_bsr = super().accept(visitor)
    return visit_bsr if visit_bsr is not None else visitor.visit_bsr_no_params(self)

BsrUnitaryParams

Bases: BlochSphereRotation

Source code in opensquirrel/ir/semantics/bsr.py 
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class BsrUnitaryParams(BlochSphereRotation):
    def __init__(
        self,
        theta: SupportsFloat,
        phi: SupportsFloat,
        lmbda: SupportsFloat,
    ) -> None:
        bsr = self.get_bsr(theta, phi, lmbda)
        BlochSphereRotation.__init__(self, bsr.axis, bsr.angle, bsr.phase)
        self.theta = Float(theta)
        self.phi = Float(phi)
        self.lmbda = Float(lmbda)

    @staticmethod
    def get_bsr(theta: SupportsFloat, phi: SupportsFloat, lmbda: SupportsFloat) -> BlochSphereRotation:
        """Generates the corresponding Bloch sphere rotation from the given Euler angles, $\\theta$,
        $\\phi$, and $\\lambda$.

        Args:
            theta (SupportsFloat): The Euler angle $\\theta$.
            phi (SupportsFloat): The Euler angle $\\phi$.
            lmbda (SupportsFloat): The Euler angle $\\lambda$.

        Returns:
            The corresponding Bloch sphere rotation.

        """
        a = BlochSphereRotation((0, 0, 1), lmbda, 0)
        b = BlochSphereRotation((0, 1, 0), theta, 0)
        c = BlochSphereRotation((0, 0, 1), phi, (float(phi) + float(lmbda)) / 2)

        ma = can1(a.axis, a.angle, a.phase)
        mb = can1(b.axis, b.angle, b.phase)
        mc = can1(c.axis, c.angle, c.phase)
        return bsr_from_matrix(mc @ mb @ ma)

    @property
    def arguments(self) -> tuple[Float, ...]:
        return self.theta, self.phi, self.lmbda

    def accept(self, visitor: IRVisitor) -> Any:
        """Accepts visitor and processes this IR node."""
        visit_bsr = super().accept(visitor)
        return visit_bsr if visit_bsr is not None else visitor.visit_bsr_unitary_params(self)

accept 

accept(visitor: IRVisitor) -> Any

Accepts visitor and processes this IR node.

Source code in opensquirrel/ir/semantics/bsr.py 
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def accept(self, visitor: IRVisitor) -> Any:
    """Accepts visitor and processes this IR node."""
    visit_bsr = super().accept(visitor)
    return visit_bsr if visit_bsr is not None else visitor.visit_bsr_unitary_params(self)

get_bsr staticmethod 

get_bsr(
    theta: SupportsFloat,
    phi: SupportsFloat,
    lmbda: SupportsFloat,
) -> BlochSphereRotation

Generates the corresponding Bloch sphere rotation from the given Euler angles, \(\theta\), \(\phi\), and \(\lambda\).

Parameters:

Name Type Description Default
theta SupportsFloat

The Euler angle \(\theta\).

 required
phi SupportsFloat

The Euler angle \(\phi\).

 required
lmbda SupportsFloat

The Euler angle \(\lambda\).

 required

Returns:

Type Description
BlochSphereRotation

The corresponding Bloch sphere rotation.
Source code in opensquirrel/ir/semantics/bsr.py 
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@staticmethod
def get_bsr(theta: SupportsFloat, phi: SupportsFloat, lmbda: SupportsFloat) -> BlochSphereRotation:
    """Generates the corresponding Bloch sphere rotation from the given Euler angles, $\\theta$,
    $\\phi$, and $\\lambda$.

    Args:
        theta (SupportsFloat): The Euler angle $\\theta$.
        phi (SupportsFloat): The Euler angle $\\phi$.
        lmbda (SupportsFloat): The Euler angle $\\lambda$.

    Returns:
        The corresponding Bloch sphere rotation.

    """
    a = BlochSphereRotation((0, 0, 1), lmbda, 0)
    b = BlochSphereRotation((0, 1, 0), theta, 0)
    c = BlochSphereRotation((0, 0, 1), phi, (float(phi) + float(lmbda)) / 2)

    ma = can1(a.axis, a.angle, a.phase)
    mb = can1(b.axis, b.angle, b.phase)
    mc = can1(c.axis, c.angle, c.phase)
    return bsr_from_matrix(mc @ mb @ ma)

bsr_from_matrix 

bsr_from_matrix(
    matrix: ArrayLike | list[list[int | DTypeLike]],
) -> BlochSphereRotation

Generates a Bloch sphere rotation from a \(2\times 2\) unitary matrix \(U(2)\).

Parameters:

Name Type Description Default
matrix ArrayLike | list[list[int | DTypeLike]]

A \(2\times 2\) unitary matrix \(U(2)\).

 required

Returns:

Type Description
BlochSphereRotation

The corresponding Bloch sphere rotation.
Source code in opensquirrel/ir/semantics/bsr.py 
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def bsr_from_matrix(matrix: ArrayLike | list[list[int | DTypeLike]]) -> BlochSphereRotation:
    """Generates a Bloch sphere rotation from a $2\\times 2$ unitary matrix $U(2)$.

    Args:
        matrix (ArrayLike | list[list[int | DTypeLike]]): A $2\\times 2$ unitary matrix $U(2)$.

    Returns:
        The corresponding Bloch sphere rotation.

    """
    cmatrix = np.asarray(matrix, dtype=np.complex128)

    if cmatrix.shape != (2, 2):
        msg = (
            f"matrix has incorrect shape for generating a Bloch sphere rotation {cmatrix.shape},"
            " required shape is (2, 2)"
        )
        raise ValueError(msg)

    a, b, c, d = map(complex, cmatrix.flatten())
    phase = cmath.phase(a * d - c * b) / 2

    a *= cmath.exp(-1j * phase)
    b *= cmath.exp(-1j * phase)
    c *= cmath.exp(-1j * phase)
    d *= cmath.exp(-1j * phase)

    angle = -2 * acos((1 / 2) * (a + d).real)
    nx = -1j * (b + c)
    ny = b - c
    nz = -1j * (a - d)

    nx, ny, nz = (x.real for x in (nx, ny, nz))

    if math.sqrt(nx**2 + ny**2 + nz**2) < ATOL:
        return BlochSphereRotation(axis=(0, 0, 1), angle=0.0, phase=phase)

    if angle <= -pi:
        angle += 2 * pi

    if nx + ny + nz < 0:
        nx = -nx
        ny = -ny
        nz = -nz
        angle = -angle
    axis = Axis((nx, ny, nz))
    return BlochSphereRotation(axis=axis, angle=angle, phase=phase)