"""This module implements the CHGate."""
from __future__ import annotations
import math
from bqskit.ir.gates.constantgate import ConstantGate
from bqskit.ir.gates.qubitgate import QubitGate
from bqskit.qis.unitary.unitarymatrix import UnitaryMatrix
[docs]
class CHGate(ConstantGate, QubitGate):
"""
The controlled-Hadamard gate.
The Controlled-H gate is given by the following unitary:
.. math::
\\begin{pmatrix}
1 & 0 & 0 & 0 \\\\
0 & 1 & 0 & 0 \\\\
0 & 0 & \\frac{\\sqrt{2}}{2} & \\frac{\\sqrt{2}}{2} \\\\
0 & 0 & \\frac{\\sqrt{2}}{2} & -\\frac{\\sqrt{2}}{2} \\\\
\\end{pmatrix}
"""
_num_qudits = 2
_qasm_name = 'ch'
_utry = UnitaryMatrix(
[
[1, 0, 0, 0],
[0, 1, 0, 0],
[0, 0, math.sqrt(2) / 2, math.sqrt(2) / 2],
[0, 0, math.sqrt(2) / 2, -math.sqrt(2) / 2],
],
)