"""This module implements the TrivialPlacementPass class."""
from __future__ import annotations
import logging
from bqskit.compiler.basepass import BasePass
from bqskit.compiler.passdata import PassData
from bqskit.ir.circuit import Circuit
_logger = logging.getLogger(__name__)
[docs]
class TrivialPlacementPass(BasePass):
"""Place the logical qubits on the first n physical qubits."""
[docs]
async def run(self, circuit: Circuit, data: PassData) -> None:
"""Perform the pass's operation, see :class:`BasePass` for more."""
# Select the first n physical qubits for placement
trivial_placement = list(range(circuit.num_qudits))
model = BasePass.get_model(circuit, data)
data['placement'] = trivial_placement
_logger.info(f'Placed qudits on {data["placement"]}')
# Raise an error if this is not a valid placement
sg = model.coupling_graph.get_subgraph(data['placement'])
if not sg.is_fully_connected():
raise RuntimeError('The trivial placement is not valid.')