Module sparse 

Sparse feature representation for high-dimensional data.

RillML uses a sorted (FeatureId, value) vector instead of HashMap<String, f64> as the core sparse representation. This keeps serialization deterministic and memory predictable.

Structs

SparseFeatures

Sparse feature vector: sorted (FeatureId, value) pairs.

Type Aliases

FeatureId

Feature identifier type. Use integers, not strings.