Struct Model 

pub struct Model {
    pub name: String,
    /* private fields */
}

The optimization model. Owns the expression arena, variable/parameter registries, constraints, and (optional) objective.

Model uses interior mutability so the builder API can take &self references.

Variables, constraints, and the objective are added through RefCells under the hood.

Fields

name: String

Implementations

impl Model

pub fn new(name: impl Into<String>) -> Self

pub fn variable_id(&self, name: &str) -> Option<VarId>

pub fn variables(&self) -> Ref<'_, Vec<Variable>>

pub fn arena(&self) -> Ref<'_, ExprArena>

pub fn num_variables(&self) -> usize

pub fn fix(&self, e: Expr<'_>, value: f64)

Fix a single-variable expression to value. Convenience over Self::fix_var for handles from the variable! macro or crate::IndexedVar indexing.

Panics

Panics if e is not a bare variable handle.

pub fn fix_var(&self, id: VarId, value: f64)

Fix variable id to value by setting lb = ub = value.

pub fn set_initial(&self, e: Expr<'_>, value: f64)

Set the initial (warm-start) value of a single-variable expression. The macro API has no bound-style syntax for warm starts, so this is the supported way to seed variable!-declared variables.

Panics

Panics if e is not a bare variable handle.

pub fn unfix_var(&self, id: VarId, lb: f64, ub: f64)

Restore bounds on variable id. Pass f64::NEG_INFINITY / f64::INFINITY to restore an unbounded direction.

pub fn set_param_idx<K, Q: Into<IndexKey>>( &self, params: &IndexedParam<'_, K>, key: Q, value: f64, )

Re-bind the parameter at key of an indexed family to value. Takes effect on the next solve.

Panics

Panics if key is not present in the family, or if params was built on a different Model.

pub fn param_value_idx<K, Q: Into<IndexKey>>( &self, params: &IndexedParam<'_, K>, key: Q, ) -> Option<f64>

Current value bound to the parameter at key of an indexed family, or None if the key is absent.

pub fn set_param(&self, p: Expr<'_>, value: f64)

Re-bind the parameter referenced by handle p to value.

Panics

Panics if p is not a bare parameter handle (one returned by the param! macro).

pub fn set_param_id(&self, id: ParamId, value: f64)

Re-bind parameter id to value. Takes effect on the next solve.

The value is stored only in the expression arena (its single source of truth); extraction and evaluation read it from there.

pub fn param_value(&self, id: ParamId) -> f64

Current value bound to parameter id.

Panics

Panics if id does not belong to a parameter registered on this model.

pub fn param_value_of(&self, p: Expr<'_>) -> Option<f64>

Current value of the parameter referenced by handle p, or None if p is not a bare parameter handle.

pub fn parameter_id(&self, name: &str) -> Option<ParamId>

pub fn parameters(&self) -> Ref<'_, Vec<Parameter>>

pub fn num_parameters(&self) -> usize

pub fn add_constraints<'a, I>(&'a self, items: I)

where I: IntoIterator<Item = (SmolStr, ConstraintExpr<'a>)>,

Bulk-register constraints. Each entry is (name, ConstraintExpr). Useful with .par_iter().map(...).collect() style construction.

pub fn constraints(&self) -> Ref<'_, Vec<Constraint>>

pub fn num_constraints(&self) -> usize

pub fn constraint_id(&self, name: &str) -> Option<ConstraintId>

pub fn add_soc_constraint<'a>( &'a self, name: impl Into<SmolStr>, terms: impl IntoIterator<Item = Expr<'a>>, bound: Expr<'a>, ) -> SocConstraintId

Register the explicit second-order cone constraint ||terms||_2 <= bound.

Every member of terms and the bound must be affine; the bound is additionally constrained to be nonnegative by the cone itself, so backends emit a bound >= 0 side condition where needed.

Panics

Panics if a SOC constraint with the same name is already registered, if terms is empty, if any term or the bound is not affine, or if the count exceeds u32::MAX.

pub fn soc_constraints(&self) -> Ref<'_, Vec<SocConstraint>>

pub fn num_soc_constraints(&self) -> usize

pub fn soc_constraint_id(&self, name: &str) -> Option<SocConstraintId>

pub fn has_cones(&self) -> bool

Whether the model carries any explicit second-order cone constraints.

pub fn is_feasibility(&self) -> bool

Whether feasibility was declared explicitly via objective!(m, Feasibility), as opposed to a model that simply has no objective set.

pub fn ensure_objective_declared(&self) -> Result<()>

Ensure the model has a solve direction declared: either an objective (Min/Max) or an explicit feasibility problem.

Errors

Returns Error::NoObjective if neither an objective nor objective!(m, Feasibility) was declared.

pub fn objective(&self) -> Ref<'_, Option<Objective>>

pub fn try_objective(&self) -> Result<Objective>

Try to get a cloned copy of the objective.

Errors

Returns Error::NoObjective if no objective is set on this model.

pub fn kind(&self) -> ModelKind

Infer the ModelKind from current variables and expressions. Result is cached and invalidated whenever variables, constraints, or the objective change.

The decision ladder, top-down (any integer variable picks the MI* column):

1. any nonlinear expression (objective or constraint) -> NLP
2. any quadratic constraint not recognized as SOC (see crate::detect_soc) -> QCP
3. cones present (explicit or detected) -> SOCP
4. quadratic objective -> QP
5. otherwise -> LP

Trait Implementations

impl Debug for Model

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.