Struct BasisBuildResult 

pub struct BasisBuildResult {
    pub design: DesignMatrix,
    pub affine_offset: Option<Array1<f64>>,
    pub active_penalties: Vec<ActivePenalty>,
    pub dropped_penalties: Vec<DroppedPenaltyInfo>,
    pub metadata: BasisMetadata,
    pub kronecker_factored: Option<KroneckerFactoredBasis>,
    pub joint_null_rotation: Option<JointNullRotation>,
}

Standardized basis build result for engine-level composition.

Fields

design: DesignMatrix

affine_offset: Option<Array1<f64>>

Fixed row-wise contribution carried by an affine basis chart.

Ordinary bases are linear in their fitted coefficients and leave this as None. An inhomogeneous boundary condition, such as a non-zero B-spline endpoint anchor, realizes the basis as offset(x) + design(x) * beta; the known offset(x) belongs here, not in a fake coefficient column. Term-collection assembly sums these channels and routes the result through the model’s ordinary likelihood offset at fit and prediction time.

active_penalties: Vec<ActivePenalty>

Canonical active penalties. Matrix, spectral metadata, operator form, and semantic identity are one record so dropping an earlier candidate cannot shift one channel without shifting all of them.

dropped_penalties: Vec<DroppedPenaltyInfo>

Candidate diagnostics excluded from the active smoothing-parameter layout. Dropped candidates never share a positional container with active matrices.

metadata: BasisMetadata

kronecker_factored: Option<KroneckerFactoredBasis>

Optional factored rowwise-Kronecker representation for tensor-product bases. When present, downstream code can keep the design operator-backed instead of forcing a fully materialized n x prod(q_j) block.

joint_null_rotation: Option<JointNullRotation>

Joint-null absorption rotation for this basis, when the basis carries any penalties with a non-trivial joint null space.

Some(rotation) records Q = [U_range | U_null] where U_null spans the joint null space null(Σ_k S_k) over this basis’s active penalties (unscaled — the structural joint null is independent of λ). After the basis pipeline applies this rotation, the design becomes X · Q and each penalty becomes Qᵀ S_k Q, block-diagonal with a guaranteed-zero null tail. The same Q must be replayed at prediction time, so it is persisted in the fitted model. None indicates either no penalties on this basis, or a full-rank joint penalty (joint nullity = 0). A Some value is never recorded with joint_nullity == 0 — the None discriminant is canonical for “nothing to absorb”.

Stage-2 commit A: this field is plumbed into the struct but neither computed nor applied yet. Stage-2 commit B populates it; Stage-2 commit D applies the rotation to design and penalties.

Trait Implementations

impl Clone for BasisBuildResult

fn clone(&self) -> BasisBuildResult

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for BasisBuildResult

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

Formats the value using the given formatter.