Struct NlpTrace 

pub struct NlpTrace {
    pub n_vars: u32,
    pub n_constraints: u32,
    pub jac_nnz: u32,
    pub hess_nnz: u32,
    pub status_code: Option<i32>,
    pub status_label: Option<String>,
    pub iterations: u32,
    pub objective: f64,
    pub final_primal_inf: Option<f64>,
    pub final_dual_inf: Option<f64>,
    pub final_mu: Option<f64>,
    pub converged: bool,
}

NLP solver stats for a single NlpSolver::solve call.

Populated by the backend on the returned NlpSolution. Carries both problem structure (size, sparsity) and termination state (status code and mnemonic, iteration count, final primal/dual residuals, barrier parameter). Enables SCUC-equivalent debugging on the AC SCED side — e.g. distinguishing a proven-infeasible solve from one that hit max_iter with small residuals.

Fields

n_vars: u32

Number of decision variables.

n_constraints: u32

Number of constraints (rows of g(x)).

jac_nnz: u32

Nonzeros in the constraint Jacobian sparsity pattern.

hess_nnz: u32

Nonzeros in the Hessian sparsity pattern (0 when Hessian is approximated, e.g. Ipopt L-BFGS mode).

status_code: Option<i32>

Raw solver status code (backend-specific). For Ipopt: 0 = Solve_Succeeded, 1 = Solved_To_Acceptable_Level, 2 = Infeasible_Problem_Detected, -1 = Maximum_Iterations_Exceeded, etc.

status_label: Option<String>

Human-readable status label (backend mnemonic), e.g. "Solve_Succeeded", "Restoration_Failed".

iterations: u32

Iteration count at termination.

objective: f64

Final objective value.

final_primal_inf: Option<f64>

Primal infeasibility at the final iterate (max constraint violation in the solver’s scaled internal representation).

final_dual_inf: Option<f64>

Dual infeasibility at the final iterate (KKT stationarity residual).

final_mu: Option<f64>

Final barrier parameter μ (Ipopt). Large μ at termination typically indicates the solver stalled before reaching the interior-point endgame.

converged: bool

Whether the solver considered the problem converged.

Trait Implementations

impl Clone for NlpTrace

fn clone(&self) -> NlpTrace

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for NlpTrace

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

Formats the value using the given formatter.

impl Default for NlpTrace

fn default() -> NlpTrace

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for NlpTrace

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for NlpTrace

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

where __S: Serializer,

Serialize this value into the given Serde serializer.