#
# GAMS - General Algebraic Modeling System Python API
#
# Copyright (c) 2023 GAMS Development Corp. <support@gams.com>
# Copyright (c) 2023 GAMS Software GmbH <support@gams.com>
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
#
from __future__ import annotations
from typing import TYPE_CHECKING
import gams.transfer as gt
from gams.core.gdx import GMS_DT_ALIAS
import gamspy as gp
import gamspy._algebra.condition as condition
import gamspy._algebra.expression as expression
import gamspy._algebra.operable as operable
import gamspy._validation as validation
from gamspy._symbols.set import SetMixin
from gamspy._symbols.symbol import Symbol
if TYPE_CHECKING:
from gamspy import Set, Container
[docs]
class Alias(gt.Alias, operable.Operable, Symbol, SetMixin):
"""
Represents an Alias symbol in GAMS.
https://www.gams.com/latest/docs/UG_SetDefinition.html#UG_SetDefinition_TheAliasStatementMultipleNamesForASet
Parameters
----------
container : Container
name : str
alias_with : Set
Examples
--------
>>> import gamspy as gp
>>> m = gp.Container()
>>> i = gp.Set(m, "i")
>>> j = gp.Alias(m, "j", i)
"""
@classmethod
def _constructor_bypass(
cls, container: Container, name: str, alias_with: Set
):
# create new symbol object
obj = Alias.__new__(cls, container, name, alias_with)
# set private properties directly
obj._requires_state_check = False
obj._container = container
container._requires_state_check = True
obj._name = name
obj._alias_with = alias_with
obj._modified = True
# typing
obj._gams_type = GMS_DT_ALIAS
obj._gams_subtype = 1
# add to container
container.data.update({name: obj})
# gamspy attributes
obj._is_dirty = False
obj.where = condition.Condition(obj)
obj.container._add_statement(obj)
obj._current_index = 0
return obj
def __new__(cls, container: Container, name: str, alias_with: Set):
if not isinstance(container, gp.Container):
raise TypeError(
"Container must of type `Container` but found"
f" {type(container)}"
)
if not isinstance(name, str):
raise TypeError(f"Name must of type `str` but found {type(name)}")
try:
symobj = container[name]
if isinstance(symobj, cls):
return symobj
raise TypeError(
f"Cannot overwrite symbol `{name}` in container"
" because it is not an Alias object)"
)
except KeyError:
return object.__new__(Alias)
def __init__(self, container: Container, name: str, alias_with: Set):
# does symbol exist
has_symbol = False
if isinstance(getattr(self, "container", None), gp.Container):
has_symbol = True
if has_symbol:
# reset some properties
self._requires_state_check = True
self.container._requires_state_check = True
self.modified = True
self.alias_with = alias_with
else:
self._is_dirty = False
name = validation.validate_name(name)
super().__init__(container, name, alias_with)
validation.validate_container(self, self.domain)
self.where = condition.Condition(self)
self.container._add_statement(self)
self._current_index = 0
self.container._run()
def __len__(self):
if self.records is not None:
return len(self.records.index)
return 0
def __next__(self):
if self._current_index < len(self):
row = self.records.iloc[self._current_index]
self._current_index += 1
return row
self._current_index = 0
raise StopIteration
def __iter__(self):
return self
def __le__(self, other):
return expression.Expression(self, "<=", other)
def __ge__(self, other):
return expression.Expression(self, ">=", other)
[docs]
def gamsRepr(self) -> str:
"""
Representation of this Alias in GAMS language.
Returns
-------
str
"""
return self.name
[docs]
def getStatement(self) -> str:
"""
Statement of the Alias definition
Returns
-------
str
"""
return f"Alias({self.alias_with.name},{self.name});"
