Source code for

# --------------------------------------------------------------------------
# Source file provided under Apache License, Version 2.0, January 2004,
# (c) Copyright IBM Corp. 2015, 2021
# --------------------------------
from enum import Enum

from import is_number, is_string

[docs]class Priority(Enum): """ This enumerated class defines the priorities: VERY_LOW, LOW, MEDIUM, HIGH, VERY_HIGH, MANDATORY. """ def __new__(cls, value, print_name): obj = object.__new__(cls) # predefined obj._value_ = value obj._print_name = print_name return obj VERY_LOW = 100, 'Very Low' LOW = 200, 'Low' MEDIUM = 300, 'Medium' HIGH = 400, 'High' VERY_HIGH = 500, 'Very High' MANDATORY = 999999999, 'Mandatory' def __repr__(self): return 'Priority<{}>'.format( @property def cplex_preference(self): return self._get_geometric_preference_factor(base=10.0) def _get_geometric_preference_factor(self, base): # INTERNAL: returns a CPLEX preference factor as a power of "base" # MEDIUM priority is the balance point with a preference of 1. assert is_number(base) if self.is_mandatory(): return 1e+20 else: # noinspection PyTypeChecker medium_index = Priority.MEDIUM.value / 100 # pylint complains about no value member but is wrong! diff = self.value / 100 - medium_index factor = 1.0 pdiff = diff if diff >= 0 else -diff for _ in range(0, int(pdiff)): factor *= base return factor if diff >= 0 else 1.0 / factor def less_than(self, other): assert isinstance(other, Priority) return self.value < other.value def __lt__(self, other): return self.less_than(other) def __gt__(self, other): return other.less_than(self) def is_mandatory(self): return self == Priority.MANDATORY @classmethod def parse(cls, arg, logger, accept_none=True, do_raise=True): ''' Converts its argument to a ``Priority`` object. Returns `default_priority` if the text is not a string, empty, or does not match. Args; arg: The argument to convert. logger: An error logger accept_none: True if None is a possible value. Typically, Constraint.set_priority accepts None as a way to remove the constraint's own priority. do_raise: A Boolean flag indicating if an exception is to be raised if the value is not recognized. Returns: A Priority enumerated object. ''' if isinstance(arg, cls): return arg elif is_string(arg): key = arg.lower() # noinspection PyTypeChecker for p in cls: if key == or key == str(p.value): return p if do_raise: logger.fatal('String does not match priority type: {}', arg) else: logger.error('String does not match priority type: {}', arg) return None return None elif accept_none and arg is None: return None else: logger.fatal('Cannot convert to a priority: {0!s}'.format(arg))
class UserPriority(object): def __init__(self, pref, name=None): assert pref >= 0 self._preference = pref self._name = name @property def cplex_preference(self): return self._preference # noinspection PyMethodMayBeStatic def is_mandatory(self): return False @property def name(self): return self._name or '_user_' @property def value(self): return self._preference def __str__(self): name = self._name sname = '%s: ' % name if name else '' return 'UserPriority({0}{1})'.format(sname, self._preference)