Struct LowRankAugSystemSolver 

pub struct LowRankAugSystemSolver { /* private fields */ }

Implementations

impl LowRankAugSystemSolver

pub fn new(inner: Box<dyn AugSystemSolver>) -> Self

pub fn augmented_system_requires_change( &self, coeffs: &AugSysCoeffs<'_>, ) -> bool

Pure tag/scalar comparison — port of upstream AugmentedSystemRequiresChange (IpLowRankAugSystemSolver.cpp:531-599).

pub fn first_call(&self) -> bool

pub fn cache(&self) -> &AugSysCache

Trait Implementations

impl AugSystemSolver for LowRankAugSystemSolver

fn provides_inertia(&self) -> bool

Whether the underlying linear solver reports inertia.

fn number_of_neg_evals(&self) -> Index

Number of negative eigenvalues observed in the most recent factorization. Caller checks provides_inertia() first.

fn increase_quality(&mut self) -> bool

Ask the underlying solver for higher-quality pivoting.

fn last_solve_status(&self) -> ESymSolverStatus

Status of the most recent solve call.

fn set_timing_stats(&mut self, timing: Rc<TimingStatistics>)

Install the shared per-solve TimingStatistics so the linear-system factor/back-solve calls are attributed to linear_system_factorization / linear_system_back_solve. Default impl is a no-op (timing disabled); the standard solver overrides to record both fields, and composite solvers (LowRank) forward to their inner solver.

fn solve( &mut self, coeffs: &AugSysCoeffs<'_>, rhs: &AugSysRhs<'_>, sol: &mut AugSysSol<'_>, check_neg_evals: bool, num_neg_evals: Index, ) -> ESymSolverStatus

One factor + back-substitution for the full 4×4 block system. check_neg_evals=true asks the linsol to verify that the observed inertia equals num_neg_evals; on mismatch the status is WrongInertia and the solution is left untouched.

fn system_dim(&self) -> Index

Dimension of the assembled augmented (KKT) system. Used by the interactive debugger to report inertia; default 0 for backends that don’t track it.

fn kkt_triplets(&self) -> Option<(Index, Vec<Index>, Vec<Index>, Vec<Number>)>

Triplets of the assembled KKT matrix (dim, irn, jcn, vals) (1-based lower triangle), for the debugger’s viz kkt. Default None for backends that don’t expose them.

fn l_factor(&self, _want_values: bool) -> Option<FactorPattern>

The LDLᵀ factor pattern (and optionally values) of the most recent factorization, for the debugger’s viz L. Default None.

fn set_diagnostics(&mut self, _diag: Rc<DiagnosticsState>)

Install the shared per-solve diagnostics state so KKT-dump sites can consult per-iter gating. Default impl is a no-op (diagnostics disabled); the standard solver overrides to wire in the dump path.

fn resolve( &mut self, coeffs: &AugSysCoeffs<'_>, rhs: &AugSysRhs<'_>, sol: &mut AugSysSol<'_>, ) -> ESymSolverStatus

Back-substitution only, reusing the factorization from the most recent successful solve. Caller must guarantee the augmented matrix is byte-identical to that solve (same W, J_c, J_d, all diagonals, all perturbations, same pivot tolerance). Used by PdFullSpaceSolver’s iterative-refinement loop and same-matrix fast path to avoid the per-iter MA57BD refactor that dominates pounce-ma57 wall time on long-iter problems (e.g. cont5_2_4_l drops from 97s → ~30s once refactor-per-refinement is gone).

fn multi_solve( &mut self, coeffs: &AugSysCoeffs<'_>, rhs_list: &[&AugSysRhs<'_>], sol_list: &mut [&mut AugSysSol<'_>], check_neg_evals: bool, num_neg_evals: Index, ) -> ESymSolverStatus

Solve the same KKT system for nrhs right-hand sides. Default impl loops [solve]; concrete backends override only when they can amortize factorization across calls. Mirrors upstream’s AugSystemSolver::MultiSolve (IpAugSystemSolver.hpp:113-150).

fn try_resolve_many_flat( &mut self, _coeffs: &AugSysCoeffs<'_>, _packed_rhs: &mut [Number], _nrhs: usize, ) -> Option<ESymSolverStatus>

Back-substitution only against the cached factor for nrhs right-hand sides, packed in column-major layout in packed_rhs. Each column has length dim = n_x + n_s + n_y_c + n_y_d (the aug-system dim — z/v blocks are not part of this path; callers expand them via expand_bound_multipliers after the fact). Solutions overwrite packed_rhs in place.