register_atomic_objective_internal: Register an atomic objective (internal)

In multiscape: Multi-Action, Multi-Objective Spatial Planning

Register an atomic objective (internal)

Description

Internal helper used by objective setter functions to define the active single-objective configuration of a Problem object and, optionally, register that objective as an atomic objective for multi-objective workflows.

Arguments

x	A Problem object.
alias	Optional character scalar used to register the objective as an atomic objective. If NULL, no registration entry is created.
objective_id	Character string giving the stable internal identifier of the objective, for example "min_cost" or "max_benefit".
model_type	Character string giving the model-builder label associated with this objective, for example "minimizeCosts".
objective_args	A list of objective-specific arguments to be stored with the objective definition.
sense	Character string giving the optimization direction. Must be either "min" or "max".

Details

In multiscape, an atomic objective is a fully specified objective definition that can later be reused by a multi-objective method such as a weighted-sum formulation, an \epsilon-constraint method, AUGMECON, or other objective-orchestration procedures.

Each atomic objective is identified by:

• a stable internal identifier objective_id,

• a solver-facing model label model_type,

• a list of objective-specific arguments stored in objective_args,

• an optimization sense, either "min" or "max",

• and, optionally, a user-facing identifier alias.

If alias is not NULL, the objective is stored in x$data$objectives[[alias]]. This makes it possible to refer to the same objective later by a stable user-facing name. For example, a user may register objectives under aliases such as "cost", "benefit", or "frag" and then pass those aliases to a multi-objective method.

If alias is NULL, no atomic-objective entry is created in x$data$objectives. In that case, the calling function still defines the currently active single-objective configuration through x$data$model_args, but no reusable multi-objective registration is created.

Thus, this helper supports two complementary modes:

• single-objective mode: only the active objective is stored,

• multi-objective-ready mode: the active objective is stored and also registered under an alias for later reuse.

Conceptually, if an objective function is denoted by f(x), this helper does not itself define the mathematical form of f; rather, it stores the metadata required so that downstream code can reconstruct the correct objective expression, its direction of optimization, and its user-visible identity.

Value

An updated Problem object.

multiscape documentation built on Oct. 12, 2026, 5:08 p.m.