Struct StreamingBorderGram 

pub struct StreamingBorderGram { /* private fields */ }

Chunked, out-of-core, bit-reproducible border-Gram accumulator.

Accumulates G = Σ_n x_n x_nᵀ ∈ ℝ^{k×k} over n_rows rows submitted as fixed-size chunks (any submission order), with f64 accumulation throughout and a deterministic pairwise reduction tree whose shape is a pure function of (n_rows, chunk_size). See the module docs for the determinism contract.

Implementations

impl StreamingBorderGram

pub fn new( border_dim: usize, n_rows: usize, chunk_size: usize, ) -> Result<Self, String>

Create an empty accumulator for n_rows total rows of border dimension border_dim, streamed in chunks of chunk_size rows.

pub fn n_chunks(&self) -> usize

Total number of chunks of the pass: ceil(n_rows / chunk_size).

pub fn chunk_rows(&self, chunk_index: usize) -> Range<usize>

Row range covered by chunk chunk_index: [chunk_index·chunk_size, min((chunk_index+1)·chunk_size, n_rows)). A pure function of the partition parameters — the caller slices its shard rows with exactly this range.

pub fn frontier(&self) -> usize

Number of chunks already consumed by the in-order cascade (the chunk cursor). Pending out-of-order chunks are not counted.

pub fn checkpoint(&self) -> BorderGramCheckpoint

Serialize the full accumulation state — partial Grams + chunk cursor — for checkpointing. StreamingBorderGram::resume reconstructs an accumulator whose future behavior is bit-identical to never having stopped.

pub fn resume(state: BorderGramCheckpoint) -> Result<Self, String>

Reconstruct an accumulator from a checkpoint. Validates the structural invariants so a corrupted checkpoint is rejected loudly instead of silently producing a wrong (but plausible-looking) Gram.

pub fn finish(self) -> Result<Array2<f64>, String>

Finish the pass, returning the k×k border Gram. Errors if any chunk is missing (out-of-order pending chunks the frontier never reached, or chunks never submitted). The result is a pure function of the row content: identical bits for any submission order and for any checkpoint/resume history.