Enum SolverDiagnostics 

#[non_exhaustive]
pub enum SolverDiagnostics {
    Lbfgs(LbfgsDiagnostics),
    Newton(NewtonDiagnostics),
    TrustRegion(TrustRegionDiagnostics),
    Other,
}

Per-solver diagnostic counters.

Each variant carries the counters that solver tracks. The enum shape (rather than a flat struct with optional fields) makes it impossible to confuse “this solver doesn’t track this counter” with “this counter genuinely observed zero”.

Marked #[non_exhaustive] so future solver additions don’t keep breaking downstream match exhaustiveness.

Example

use echidna_optim::{lbfgs, LbfgsConfig, SolverDiagnostics, TerminationReason};
let result = lbfgs(&mut obj, &x0, &LbfgsConfig::default());
if let SolverDiagnostics::Lbfgs(d) = &result.diagnostics {
    if result.termination == TerminationReason::GradientNorm
       && d.pairs_curvature_rejected > d.pairs_accepted
    {
        eprintln!("L-BFGS converged but ran mostly as steepest descent — \
                   consider a different solver or rescale the problem");
    }
}

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Lbfgs(LbfgsDiagnostics)

L-BFGS-specific counters.

Newton(NewtonDiagnostics)

Newton-specific counters.

TrustRegion(TrustRegionDiagnostics)

Trust-region-specific counters.

Other

Fallback for solver paths that don’t yet emit specific counters.

Implementations

impl SolverDiagnostics

pub fn as_lbfgs(&self) -> Option<&LbfgsDiagnostics>

Returns the L-BFGS counters if this result came from lbfgs.

pub fn as_newton(&self) -> Option<&NewtonDiagnostics>

Returns the Newton counters if this result came from newton.

pub fn as_trust_region(&self) -> Option<&TrustRegionDiagnostics>

Returns the trust-region counters if this result came from trust_region.

Trait Implementations

impl Clone for SolverDiagnostics

fn clone(&self) -> SolverDiagnostics

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for SolverDiagnostics

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

Formats the value using the given formatter.