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from typing import Any, Sequence
from braket.circuits.quantum_operator import QuantumOperator
from braket.circuits.qubit_set import QubitSet
[docs]class Gate(QuantumOperator):
"""
Class `Gate` represents a quantum gate that operates on N qubits. Gates are considered the
building blocks of quantum circuits. This class is considered the gate definition containing
the metadata that defines what a gate is and what it does.
"""
def __init__(self, qubit_count: int, ascii_symbols: Sequence[str]):
"""
Args:
qubit_count (int): Number of qubits this gate interacts with.
ascii_symbols (Sequence[str]): ASCII string symbols for the gate. These are used when
printing a diagram of circuits. Length must be the same as `qubit_count`, and
index ordering is expected to correlate with target ordering on the instruction.
For instance, if CNOT instruction has the control qubit on the first index and
target qubit on the second index. Then ASCII symbols would have ["C", "X"] to
correlate a symbol with that index.
Raises:
ValueError: `qubit_count` is less than 1, `ascii_symbols` are None, or
`ascii_symbols` length != `qubit_count`
"""
super().__init__(qubit_count=qubit_count, ascii_symbols=ascii_symbols)
[docs] def to_ir(self, target: QubitSet) -> Any:
"""Returns IR object of quantum operator and target
Args:
target (QubitSet): target qubit(s)
Returns:
IR object of the quantum operator and target
"""
raise NotImplementedError("to_ir has not been implemented yet.")
def __eq__(self, other):
if isinstance(other, Gate):
return self.name == other.name
return NotImplemented
def __repr__(self):
return f"{self.name}('qubit_count': {self.qubit_count})"
[docs] @classmethod
def register_gate(cls, gate: "Gate"):
"""Register a gate implementation by adding it into the Gate class.
Args:
gate (Gate): Gate class to register.
"""
setattr(cls, gate.__name__, gate)