Source code for pytket.passes.passselector

# Copyright 2019-2024 Cambridge Quantum Computing
# Licensed under the Apache License, Version 2.0 (the "License");
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from typing import Optional, Callable

from pytket.circuit import Circuit
from .._tket.passes import BasePass

[docs]class PassSelector: """ Collection of pytket compilation passes which are all applied to the same circuit. The result of the compilation is the best circuit as selected by a given metric. """
[docs] def __init__( self, passlist: list[BasePass], score_func: Callable[[Circuit], int], ): """ Constructs a PassSelector :param passlist: list of pytket compilation passes :param score_func: function to score the results of the compilation (lower scores are preferred) """ self._passlist = passlist self._score_func = score_func if len(self._passlist) < 1: raise ValueError("passlist needs to contain at least one pass")
[docs] def apply(self, circ: Circuit) -> Circuit: """ Compiles the given circuit with the best of the given passes. :param circ: Circuit that should be compiled :return: compiled circuit """ circ_list = [circ.copy() for _ in self._passlist] self._scores: list[Optional[int]] = [] for p, c in zip(self._passlist, circ_list): try: p.apply(c) self._scores.append(self._score_func(c)) except: # in case of any error the pass should be ignored self._scores.append(None) try: return circ_list[ self._scores.index(min(x for x in self._scores if x is not None)) ] except ValueError: raise RuntimeError("No passes have successfully run on this circuit")
[docs] def get_scores(self) -> list[Optional[int]]: """ :return: scores of the circuit after compiling for each of the compilations passes """ return self._scores