Struct SolutionInfo 

pub struct SolutionInfo {
    pub engine: String,
    pub status: ApplicationReturnStatus,
    pub status_upstream: String,
    pub solve_result_num: i32,
    pub objective: f64,
    pub x: Vec<f64>,
    pub lambda: Vec<f64>,
    pub suffixes: Vec<SolutionSuffix>,
}

Fields

engine: String

Which engine produced this verdict: "cvx-qp", "cvx-qcqp", "qp-active-set", "sqp-active-set" or "nlp".

"qp-active-set" and "sqp-active-set" are different engines and not synonyms: the first is pounce_convex::active_set reached by solver_selection=qp-active-set on an LP or convex QP, the second is pounce_algorithm::sqp’s outer loop reached by algorithm=active-set-sqp on a general NLP. Both solve their subproblems with pounce-qp, which is why the names are close; they wrap it in different algorithms, which is why they are not the same string.

The Selected solver: banner names the engine routing chose, which is not always the one that answered: a convex solve that declines its own result hands the model to the NLP arm (gh #535), and the banner has already been printed by then. scripts/sweep-fixtures.sh scraped that banner because the report carried nothing better, so a reroute left no trace in the sweep diff — the precise blind spot CLAUDE.md names when it says a routing regression “used to leave no trace”.

Empty when a path does not set it, which a consumer should read as “unknown” rather than as any particular arm.

status: ApplicationReturnStatus

SolveSucceeded, MaximumIterationsExceeded, etc. The string form is the Rust enum variant name verbatim.

status_upstream: String

The same verdict in upstream Ipopt’s C enumerator spelling — Solve_Succeeded, Infeasible_Problem_Detected — from IpReturnCodes_inc.h.

Self::status carries the Rust variant name, which is not the name any Ipopt-facing consumer already keys off: CUTEst status tables, benchmarks/scripts/run_nl_bench.sh, the reference JSONs under benchmarks/*/ipopt_ma57.json and the CLI’s own Status: line all spell it with separators. A consumer comparing solution.status == "Solve_Succeeded" against the report matched nothing and silently classified every solve as a failure (gh #767). This field is that spelling, so the comparison can be literal.

Derived from Self::status by ReportBuilder::finish — never set by a caller, so the two cannot disagree. Empty when read back from a pre-#767 report.

solve_result_num: i32

AMPL-style solve-result code (Gay 2005, §5 p. 23 table).

objective: f64

Final unscaled objective value (mirrors SolveStatistics::final_objective). NaN if unknown.

x: Vec<f64>

Final primal vector, length problem.n_variables. Empty if not captured.

lambda: Vec<f64>

Final dual (constraint multiplier) vector, length problem.n_constraints.

suffixes: Vec<SolutionSuffix>

Optional sIPOPT-style suffix blocks (sens_sol_state_1 etc.). Stored as a flat map keyed by suffix name → list of (index, value) pairs, matching the AMPL .sol shape. Empty when no sensitivity / reduced-Hessian step ran.

Trait Implementations

impl Clone for SolutionInfo

fn clone(&self) -> SolutionInfo

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SolutionInfo

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for SolutionInfo

fn deserialize<__D>( __deserializer: __D, ) -> Result<SolutionInfo, <__D as Deserializer<'de>>::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for SolutionInfo

fn serialize<__S>( &self, __serializer: __S, ) -> Result<<__S as Serializer>::Ok, <__S as Serializer>::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.