Struct ArrowSchurInnerConfig 

pub struct ArrowSchurInnerConfig {
    pub n_rows: usize,
    pub latent_dim: usize,
    pub n_beta: usize,
    pub build: Arc<dyn Fn(&Array1<f64>) -> Option<ArrowSchurSystem> + Send + Sync>,
    pub solver_mode: Option<ArrowSolverMode>,
    pub streaming_chunk_size: Option<usize>,
    pub trust_region_radius: f64,
    pub block_offsets: Option<Arc<[Range<usize>]>>,
    pub apply_delta_t: Arc<dyn Fn(&Array1<f64>) + Send + Sync>,
    pub snapshot_t: Arc<dyn Fn() -> Array1<f64> + Send + Sync>,
    pub restore_t: Arc<dyn Fn(&Array1<f64>) + Send + Sync>,
}

Per-iteration arrow-Schur builder hook.

The driver supplies a closure that, given the current β iterate, returns a freshly-populated crate::arrow_schur::ArrowSchurSystem — i.e. the per-row H_tt^(i), H_tβ^(i), g_t^(i) blocks and the β-block H_ββ, g_β. The driver owns the assembly because the per-row Jacobians depend on the latent-coord term’s basis (Duchon, Sphere, …) and the analytic-penalty contributions depend on the registry the outer-fit configuration owns. PIRLS only knows how to solve the bordered system once it has been assembled.

Fields

n_rows: usize

Number of latent rows N.

latent_dim: usize

Latent dimensionality d.

n_beta: usize

β dimensionality K (must match the inner Hessian dimension).

build: Arc<dyn Fn(&Array1<f64>) -> Option<ArrowSchurSystem> + Send + Sync>

Closure that builds the bordered system at the current β and current latent t (the latter held externally by the driver, e.g. in a LatentCoordValues registered alongside the working model). Returning None signals “fall back to the β-only path for this iteration” — useful for the seeding sweep before t has been initialized.

solver_mode: Option<ArrowSolverMode>

BA Schur solve mode. None selects Direct for K <= 2000 and InexactPCG above, following “Bundle Adjustment in the Large”.

streaming_chunk_size: Option<usize>

When set, assemble the reduced dense Schur block in row chunks.

trust_region_radius: f64

Steihaug trust-region radius for the reduced shared step. This ports the Ceres/BA trust-region guard while retaining PIRLS’s LM damping.

block_offsets: Option<Arc<[Range<usize>]>>

Optional β-block column ranges for the block-Jacobi Schur preconditioner.

When Some, the PIRLS driver calls crate::arrow_schur::ArrowSchurSystem::set_block_offsets on every system returned by the build closure, wiring the block-Jacobi path without requiring each family’s closure to call it manually.

Derive from ParameterBlockSpec slices via gam_custom_family::block_offsets_from_specs. When None, the preconditioner falls back to scalar-diagonal Jacobi (the pre-#287 behaviour); when Some([]) (empty slice), the same fallback applies.

apply_delta_t: Arc<dyn Fn(&Array1<f64>) + Send + Sync>

Callback that the inner solver invokes after each LM-attempted joint step to write the latent tangent increment back into the driver’s LatentCoordValues via that latent’s update rule (retract_flat_delta for manifold latents). delta_t is the flat row-major increment of length n_rows * latent_dim.

snapshot_t: Arc<dyn Fn() -> Array1<f64> + Send + Sync>

Snapshot the driver’s latent field before an LM trial step mutates it.

restore_t: Arc<dyn Fn(&Array1<f64>) + Send + Sync>

Restore a snapshot produced by Self::snapshot_t after any rejected LM trial. Accepted trials deliberately do not call this hook: β and t commit together.

Trait Implementations

impl Clone for ArrowSchurInnerConfig

fn clone(&self) -> ArrowSchurInnerConfig

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ArrowSchurInnerConfig

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

Formats the value using the given formatter.