simopt.models.mm1queue ====================== .. py:module:: simopt.models.mm1queue .. autoapi-nested-parse:: Simulate an M/M/1 queue. Module Contents --------------- .. py:class:: MM1QueueConfig Bases: :py:obj:`pydantic.BaseModel` Configuration model for MM1 Queue simulation. A model that simulates an M/M/1 queue with an Exponential(lambda) interarrival time distribution and an Exponential(x) service time distribution. Returns: - the average sojourn time - the average waiting time - the fraction of customers who wait for customers after a warmup period. .. py:attribute:: lambda_ :type: Annotated[float, Field(default=1.5, description='rate parameter of interarrival time distribution', gt=0, alias='lambda')] .. py:attribute:: mu :type: Annotated[float, Field(default=3.0, description='rate parameter of service time distribution', gt=0)] .. py:attribute:: epsilon :type: Annotated[float, Field(default=0.001, description='the minimum value of mu', gt=0)] .. py:attribute:: warmup :type: Annotated[int, Field(default=20, description='number of people as warmup before collecting statistics', ge=0)] .. py:attribute:: people :type: Annotated[int, Field(default=50, description='number of people from which to calculate the average sojourn time', ge=1)] .. py:class:: MM1MinMeanSojournTimeConfig Bases: :py:obj:`pydantic.BaseModel` Configuration model for MM1 Min Mean Sojourn Time Problem. Min Mean Sojourn Time for MM1 Queue simulation-optimization problem. .. py:attribute:: initial_solution :type: Annotated[tuple[float, Ellipsis], Field(default=(5, ), description='initial solution from which solvers start')] .. py:attribute:: budget :type: Annotated[int, Field(default=1000, description='max # of replications for a solver to take', gt=0, json_schema_extra={'isDatafarmable': False})] .. py:attribute:: cost :type: Annotated[float, Field(default=0.1, description='cost for increasing service rate', gt=0)] .. py:class:: MM1Queue(fixed_factors: dict | None = None) Bases: :py:obj:`simopt.base.Model` MM1 Queue Simulation Model. A model that simulates an M/M/1 queue with an Exponential(lambda) interarrival time distribution and an Exponential(x) service time distribution. Returns: - the average sojourn time - the average waiting time - the fraction of customers who wait for customers after a warmup period. Initialize the MM1Queue model. :param fixed_factors: fixed factors of the simulation model. Defaults to None. :type fixed_factors: dict, optional .. py:attribute:: class_name_abbr :type: ClassVar[str] :value: 'MM1' Short name of the model class. .. py:attribute:: class_name :type: ClassVar[str] :value: 'MM1 Queue' Long name of the model class. .. py:attribute:: config_class :type: ClassVar[type[pydantic.BaseModel]] Configuration class for the model. .. py:attribute:: n_rngs :type: ClassVar[int] :value: 2 Number of RNGs used to run a simulation replication. .. py:attribute:: n_responses :type: ClassVar[int] :value: 3 Number of responses (performance measures). .. py:attribute:: arrival_model .. py:attribute:: service_model .. py:method:: before_replicate(rng_list: list[mrg32k3a.mrg32k3a.MRG32k3a]) -> None Prepare the model just before generating a replication. :param rng_list: RNGs used to drive the simulation. :type rng_list: list[MRG32k3a] :raises NotImplementedError: If the subclass does not implement this hook. .. py:method:: replicate() -> tuple[dict, dict] Simulate a single replication for the current model factors. :param rng_list: Random number generators used to simulate the replication. :type rng_list: list[MRG32k3a] :returns: A tuple containing: - responses (dict): Performance measures of interest, including: - "avg_sojourn_time": Average sojourn time. - "avg_waiting_time": Average waiting time. - "frac_cust_wait": Fraction of customers who wait. - gradients (dict): A dictionary of gradient estimates for each response. :rtype: tuple[dict, dict] .. py:class:: MM1MinMeanSojournTime(name: str = '', fixed_factors: dict | None = None, model_fixed_factors: dict | None = None) Bases: :py:obj:`simopt.base.Problem` Base class to implement simulation-optimization problems. Initialize a problem object. :param name: Name of the problem. :type name: str :param fixed_factors: Dictionary of user-specified problem factors. :type fixed_factors: dict | None :param model_fixed_factors: Subset of user-specified non-decision factors passed to the model. :type model_fixed_factors: dict | None .. py:attribute:: class_name_abbr :type: ClassVar[str] :value: 'MM1-1' Short name of the problem class. .. py:attribute:: class_name :type: ClassVar[str] :value: 'Min Mean Sojourn Time for MM1 Queue' Long name of the problem class. .. py:attribute:: config_class :type: ClassVar[type[pydantic.BaseModel]] Configuration class for problem. .. py:attribute:: model_class :type: ClassVar[type[simopt.base.Model]] Simulation model class for problem. .. py:attribute:: n_objectives :type: ClassVar[int] :value: 1 Number of objectives. .. py:attribute:: n_stochastic_constraints :type: ClassVar[int] :value: 0 Number of stochastic constraints. .. py:attribute:: minmax :type: ClassVar[tuple[int, Ellipsis]] Indicators of maximization (+1) or minimization (-1) for each objective. .. py:attribute:: constraint_type :type: ClassVar[simopt.base.ConstraintType] Description of constraints types. .. py:attribute:: variable_type :type: ClassVar[simopt.base.VariableType] Description of variable types. .. py:attribute:: gradient_available :type: ClassVar[bool] :value: True Indicates whether the solver provides direct gradient information. .. py:attribute:: optimal_value :type: ClassVar[float | None] :value: None Optimal objective function value (if known). .. py:attribute:: optimal_solution :type: tuple | None :value: None Optimal solution if known; defaults to None. .. py:attribute:: model_default_factors :type: ClassVar[dict] Default values for overriding model-level default factors. .. py:attribute:: model_decision_factors :type: ClassVar[set[str]] Set of keys for factors that are decision variables. .. py:property:: dim :type: int Number of decision variables. .. py:property:: lower_bounds :type: tuple Lower bound for each decision variable. .. py:property:: upper_bounds :type: tuple Upper bound for each decision variable. .. py:method:: vector_to_factor_dict(vector: tuple) -> dict Convert a vector of variables to a dictionary with factor keys. :param vector: A vector of values associated with decision variables. :type vector: tuple :returns: Dictionary with factor keys and associated values. :rtype: dict .. py:method:: factor_dict_to_vector(factor_dict: dict) -> tuple Convert a dictionary with factor keys to a vector of variables. :param factor_dict: Dictionary with factor keys and associated values. :type factor_dict: dict :returns: Vector of values associated with decision variables. :rtype: tuple .. py:method:: replicate(x: tuple) -> simopt.base.RepResult Replicate the problem for a given solution. :param x: The solution to evaluate. :type x: tuple .. py:method:: get_random_solution(rand_sol_rng: mrg32k3a.mrg32k3a.MRG32k3a) -> tuple Generate a random solution for starting or restarting solvers. :param rand_sol_rng: Random number generator used to sample the solution. :type rand_sol_rng: MRG32k3a :returns: A tuple representing a randomly generated vector of decision variables. :rtype: tuple