# ___________________________________________________________________________
#
# Pyomo: Python Optimization Modeling Objects
# Copyright (c) 2008-2024
# National Technology and Engineering Solutions of Sandia, LLC
# Under the terms of Contract DE-NA0003525 with National Technology and
# Engineering Solutions of Sandia, LLC, the U.S. Government retains certain
# rights in this software.
# This software is distributed under the 3-clause BSD License.
# ___________________________________________________________________________
from pyomo.core.expr.numvalue import is_numeric_data, NumericValue
from pyomo.core.kernel.base import ICategorizedObject
from pyomo.core.kernel.container_utils import define_simple_containers
class IParameter(ICategorizedObject, NumericValue):
"""The interface for mutable numeric data."""
__slots__ = ()
def __call__(self, exception=True):
"""Computes the numeric value of this object."""
raise NotImplementedError # pragma:nocover
#
# Implement the NumericValue abstract methods
#
def is_constant(self):
"""A boolean indicating that this parameter is constant."""
return False
def is_parameter_type(self):
"""A boolean indicating that this is a parameter object."""
#
# The semantics of ParamData and parameter are different.
# By default, ParamData are immutable. Hence, we treat the
# parameter objects as non-parameter data ... for now.
#
return False
def is_variable_type(self):
"""A boolean indicating that this is a variable object."""
return False
def is_fixed(self):
"""A boolean indicating that this parameter is fixed."""
return True
def is_potentially_variable(self):
"""Returns :const:`False` because this object can
never reference variables."""
return False
def polynomial_degree(self):
"""Always return zero because we always validate
that the stored expression can never reference
variables."""
return 0
[docs]class parameter(IParameter):
"""A object for storing a mutable, numeric value that
can be used to build a symbolic expression."""
_ctype = IParameter
__slots__ = ("_parent", "_storage_key", "_active", "_value", "__weakref__")
def __init__(self, value=None):
self._parent = None
self._storage_key = None
self._active = True
self._value = value
#
# Implement the IParameter abstract methods
#
def __call__(self, exception=True):
"""Computes the numeric value of this object."""
return self.value
#
# Interface
#
@property
def value(self):
"""The value of the parameter"""
return self._value
@value.setter
def value(self, value):
self._value = value
[docs]class functional_value(IParameter):
"""An object for storing a numeric function that can be
used in a symbolic expression.
Note that models making use of this object may require
the dill module for serialization.
"""
_ctype = IParameter
__slots__ = ("_parent", "_storage_key", "_active", "_fn", "__weakref__")
def __init__(self, fn=None):
self._parent = None
self._storage_key = None
self._active = True
self._fn = fn
#
# Implement the IParameter abstract methods
#
def __call__(self, exception=True):
if self._fn is None:
return None
try:
val = self._fn()
except Exception as e:
if exception:
raise e
else:
return None
# this exception should never be masked
if not is_numeric_data(val):
raise TypeError("Functional value is not numeric data")
return val
#
# Interface
#
@property
def fn(self):
"""The function stored with this object"""
return self._fn
@fn.setter
def fn(self, fn):
self._fn = fn
# inserts class definitions for simple _tuple, _list, and
# _dict containers into this module
define_simple_containers(globals(), "parameter", IParameter)