"""Defines templates representing logical qubits and its constituent parts."""
from typing import Sequence
import numpy
import numpy.typing as npt
from typing_extensions import override
from tqec.templates.base import BorderIndices, RectangularTemplate
from tqec.templates.enums import TemplateBorder
from tqec.utils.exceptions import TQECException
from tqec.utils.scale import LinearFunction, PlaquetteScalable2D
[docs]
class QubitTemplate(RectangularTemplate):
"""An error-corrected qubit.
The below text represents this template for an input ``k == 2`` ::
1 5 6 5 6 2
7 9 10 9 10 11
8 10 9 10 9 12
7 9 10 9 10 11
8 10 9 10 9 12
3 13 14 13 14 4
"""
[docs]
@override
def instantiate(
self, k: int, plaquette_indices: Sequence[int] | None = None
) -> npt.NDArray[numpy.int_]:
if plaquette_indices is None:
plaquette_indices = list(range(1, self.expected_plaquettes_number + 1))
ret = numpy.zeros(self.shape(k).to_numpy_shape(), dtype=numpy.int_)
# The four corners
ret[0, 0] = plaquette_indices[0]
ret[0, -1] = plaquette_indices[1]
ret[-1, 0] = plaquette_indices[2]
ret[-1, -1] = plaquette_indices[3]
# The up side
ret[0, 1:-1:2] = plaquette_indices[4]
ret[0, 2:-1:2] = plaquette_indices[5]
# The left side
ret[1:-1:2, 0] = plaquette_indices[6]
ret[2:-1:2, 0] = plaquette_indices[7]
# The center
ret[1:-1:2, 1:-1:2] = plaquette_indices[8]
ret[2:-1:2, 2:-1:2] = plaquette_indices[8]
ret[1:-1:2, 2:-1:2] = plaquette_indices[9]
ret[2:-1:2, 1:-1:2] = plaquette_indices[9]
# The right side
ret[1:-1:2, -1] = plaquette_indices[10]
ret[2:-1:2, -1] = plaquette_indices[11]
# The bottom side
ret[-1, 1:-1:2] = plaquette_indices[12]
ret[-1, 2:-1:2] = plaquette_indices[13]
return ret
@property
@override
def scalable_shape(self) -> PlaquetteScalable2D:
return PlaquetteScalable2D(LinearFunction(2, 2), LinearFunction(2, 2))
@property
@override
def expected_plaquettes_number(self) -> int:
return 14
[docs]
@override
def get_border_indices(self, border: TemplateBorder) -> BorderIndices:
match border:
case TemplateBorder.TOP:
return BorderIndices(1, 5, 6, 2)
case TemplateBorder.BOTTOM:
return BorderIndices(3, 13, 14, 4)
case TemplateBorder.LEFT:
return BorderIndices(1, 7, 8, 3)
case TemplateBorder.RIGHT:
return BorderIndices(2, 11, 12, 4)
class QubitSpatialCubeTemplate(RectangularTemplate):
"""An error-corrected qubit that has all the spatial boundaries in the same basis.
The below text represents this template for an input ``k == 4`` ::
1 9 10 9 10 9 10 9 10 2
11 5 17 13 17 13 17 13 6 21
12 20 13 17 13 17 13 17 14 22
11 16 20 13 17 13 17 14 18 21
12 20 16 20 13 17 14 18 14 22
11 16 20 16 19 15 18 14 18 21
12 20 16 19 15 19 15 18 14 22
11 16 19 15 19 15 19 15 18 21
12 7 15 19 15 19 15 19 8 22
3 23 24 23 24 23 24 23 24 4
Warning:
For ``k == 1``, this template does not include any of the plaquette
that have an index in ``[13, 17]`` and so its instantiation has a "hole"
in the plaquette indices.
"""
@override
def instantiate(
self, k: int, plaquette_indices: Sequence[int] | None = None
) -> npt.NDArray[numpy.int_]:
if plaquette_indices is None:
plaquette_indices = list(range(1, self.expected_plaquettes_number + 1))
shape = self.shape(k)
ret = numpy.zeros(shape.to_numpy_shape(), dtype=numpy.int_)
size = shape.x
# The four corners
ret[0, 0] = plaquette_indices[0]
ret[0, -1] = plaquette_indices[1]
ret[-1, 0] = plaquette_indices[2]
ret[-1, -1] = plaquette_indices[3]
# The up side
ret[0, 1:-1:2] = plaquette_indices[8]
ret[0, 2:-1:2] = plaquette_indices[9]
# The left side
ret[1:-1:2, 0] = plaquette_indices[10]
ret[2:-1:2, 0] = plaquette_indices[11]
# The center, which is the complex part.
# Plaquette indices between 12 and 15 (both inclusive) are for plaquettes
# on positions where (i + j) is even. Plaquettes indices between 16 and
# 19 (both inclusive) are for plaquettes on positions where (i + j) is
# odd. This is represented by an offset when (i + j) is odd.
for i in range(1, size - 1):
for j in range(1, size - 1):
offset = 4 if (i + j) % 2 == 1 else 0
# If the cell represented by (i, j) is:
# - on the top (above the main diagonal and above the anti-diagonal)
if i <= j and i <= (size - 1 - j):
ret[i, j] = plaquette_indices[12 + offset]
# - on the right (above the main diagonal and below the anti-diagonal)
elif i < j and i > (size - 1 - j):
ret[i, j] = plaquette_indices[13 + offset]
# - on the bottom (below the main diagonal and below the anti-diagonal)
elif i >= j and i >= (size - 1 - j):
ret[i, j] = plaquette_indices[14 + offset]
# - on the left (below the main diagonal and above the anti-diagonal)
elif i > j and i < (size - 1 - j):
ret[i, j] = plaquette_indices[15 + offset]
ret[1, 1] = plaquette_indices[4]
ret[1, -2] = plaquette_indices[5]
ret[-2, 1] = plaquette_indices[6]
ret[-2, -2] = plaquette_indices[7]
# The right side
ret[1:-1:2, -1] = plaquette_indices[20]
ret[2:-1:2, -1] = plaquette_indices[21]
# The bottom side
ret[-1, 1:-1:2] = plaquette_indices[22]
ret[-1, 2:-1:2] = plaquette_indices[23]
return ret
@property
@override
def scalable_shape(self) -> PlaquetteScalable2D:
return PlaquetteScalable2D(LinearFunction(2, 2), LinearFunction(2, 2))
@property
@override
def expected_plaquettes_number(self) -> int:
return 24
@override
def get_border_indices(self, border: TemplateBorder) -> BorderIndices:
match border:
case TemplateBorder.TOP:
return BorderIndices(1, 9, 10, 2)
case TemplateBorder.BOTTOM:
return BorderIndices(3, 23, 24, 4)
case TemplateBorder.LEFT:
return BorderIndices(1, 11, 12, 3)
case TemplateBorder.RIGHT:
return BorderIndices(2, 21, 22, 4)
class QubitVerticalBorders(RectangularTemplate):
"""Two vertical sides of neighbouring error-corrected qubits glued
together.
The below text represents this template for an input ``k == 2`` ::
1 2
5 7
6 8
5 7
6 8
3 4
"""
@override
def instantiate(
self, k: int, plaquette_indices: Sequence[int] | None = None
) -> npt.NDArray[numpy.int_]:
if plaquette_indices is None:
plaquette_indices = list(range(1, self.expected_plaquettes_number + 1))
ret = numpy.zeros(self.shape(k).to_numpy_shape(), dtype=numpy.int_)
# The four corners
ret[0, 0] = plaquette_indices[0]
ret[0, -1] = plaquette_indices[1]
ret[-1, 0] = plaquette_indices[2]
ret[-1, -1] = plaquette_indices[3]
# The left side
ret[1:-1:2, 0] = plaquette_indices[4]
ret[2:-1:2, 0] = plaquette_indices[5]
# The right side
ret[1:-1:2, -1] = plaquette_indices[6]
ret[2:-1:2, -1] = plaquette_indices[7]
return ret
@property
@override
def scalable_shape(self) -> PlaquetteScalable2D:
"""Returns a scalable version of the template shape."""
return PlaquetteScalable2D(LinearFunction(0, 2), LinearFunction(2, 2))
@property
@override
def expected_plaquettes_number(self) -> int:
return 8
@override
def get_border_indices(self, border: TemplateBorder) -> BorderIndices:
match border:
case TemplateBorder.TOP | TemplateBorder.BOTTOM:
raise TQECException(
f"Template {self.__class__.__name__} does not have repeating "
f"elements on the {border.name} border."
)
case TemplateBorder.LEFT:
return BorderIndices(1, 5, 6, 3)
case TemplateBorder.RIGHT:
return BorderIndices(2, 7, 8, 4)
class QubitHorizontalBorders(RectangularTemplate):
"""Two horizontal sides of neighbouring error-corrected qubits glued
together.
The below text represents this template for an input ``k == 2`` ::
1 5 6 5 6 2
3 7 8 7 8 4
"""
@override
def instantiate(
self, k: int, plaquette_indices: Sequence[int] | None = None
) -> npt.NDArray[numpy.int_]:
if plaquette_indices is None:
plaquette_indices = list(range(1, self.expected_plaquettes_number + 1))
ret = numpy.zeros(self.shape(k).to_numpy_shape(), dtype=numpy.int_)
# The four corners
ret[0, 0] = plaquette_indices[0]
ret[0, -1] = plaquette_indices[1]
ret[-1, 0] = plaquette_indices[2]
ret[-1, -1] = plaquette_indices[3]
# The up side
ret[0, 1:-1:2] = plaquette_indices[4]
ret[0, 2:-1:2] = plaquette_indices[5]
# The bottom side
ret[-1, 1:-1:2] = plaquette_indices[6]
ret[-1, 2:-1:2] = plaquette_indices[7]
return ret
@property
@override
def scalable_shape(self) -> PlaquetteScalable2D:
return PlaquetteScalable2D(LinearFunction(2, 2), LinearFunction(0, 2))
@property
@override
def expected_plaquettes_number(self) -> int:
return 8
@override
def get_border_indices(self, border: TemplateBorder) -> BorderIndices:
match border:
case TemplateBorder.TOP:
return BorderIndices(1, 5, 6, 2)
case TemplateBorder.BOTTOM:
return BorderIndices(3, 7, 8, 4)
case TemplateBorder.LEFT | TemplateBorder.RIGHT:
raise TQECException(
f"Template {self.__class__.__name__} does not have repeating "
f"elements on the {border.name} border."
)