Struct DcPoissonStats 

pub struct DcPoissonStats {
    pub k: usize,
    pub num_features: usize,
    pub membership: Vec<usize>,
    pub gene_sum: Vec<f64>,
    pub size_sum: Vec<f64>,
    pub log_gene: Vec<f32>,
    pub log_size_offset: Vec<f32>,
}

Sufficient statistics with cached log quantities for O(K · nnz(row)) scoring.

gene_sum[g·K + k] = Σ_{e : z_e = k} y_eg; size_sum[k] = Σ_{e : z_e = k} s_e. The per-feature tables are laid out feature-major (g·K + k): scoring one entity walks its nonzero features once and, for each, reads the K group values side by side, instead of striding across a K × M table once per candidate group. Use DcPoissonStats::idx to address them. Log caches score every non-current block with no log; the current block’s leave-one-out score takes one fast_ln per nonzero feature, and delta_move refreshes the logs of the columns a move touches.

Log caches are f32 — values live in roughly [-20, +25] (dominated by -ln(LOG_EPS) at the floor), and scoring is noise-dominated so f32’s ~7-digit precision is ample. Halves the largest allocation versus f64.

Fields

k: usize

num_features: usize

membership: Vec<usize>

gene_sum: Vec<f64>

Feature-major M × K: entry g·K + k.

size_sum: Vec<f64>

log_gene: Vec<f32>

Feature-major M × K: entry g·K + k.

log_size_offset: Vec<f32>

Implementations

impl DcPoissonStats

pub fn idx(&self, k: usize, g: usize) -> usize

Index of (group k, feature g) in gene_sum / log_gene.

pub fn from_profiles( profiles: &Profiles, k: usize, membership: &[usize], ) -> Self

pub fn delta_move( &mut self, e: usize, k_from: usize, k_to: usize, profiles: &Profiles, )

Apply an entity’s reassignment and refresh only the affected log entries.

Trait Implementations

impl Clone for DcPoissonStats

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.