Struct RefinementDiagnostics 

pub struct RefinementDiagnostics {
    pub anorm_1: f64,
    pub kappa_1_est: f64,
    pub steps: Vec<RefinementStep>,
    pub returned_step: usize,
}

Diagnostic data returned by solve_sparse_refined_with_diagnostics.

kappa_1_est is computed once per refinement run via the Hager–Higham 1-norm power iteration (3–5 extra solves) — it depends only on A and its factor, not on the residual or x. Per-step forward_error_bound values multiply this constant against the trajectory’s relative residual.

This is the F2.3 deliverable from dev/plans/kkt-feature-gaps.md: diagnostic emission only, no behavior change. The non-diagnostic solve_sparse_refined continues to make the identical control-flow choices.

Fields

anorm_1: f64

Exact ||A||_1 (single linear pass over the CSC values).

kappa_1_est: f64

Hager–Higham estimate of ||A||_1 · ||A^{-1}||_1. A statistical lower bound; see dev/research/condition-estimate.md.

steps: Vec<RefinementStep>

Per-step residual / forward-error trajectory. steps[0] is the unrefined solve.

returned_step: usize

Index into steps whose iterate is returned (best ||r||_2).

Trait Implementations

impl Clone for RefinementDiagnostics

fn clone(&self) -> RefinementDiagnostics

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for RefinementDiagnostics

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

Formats the value using the given formatter.