Struct RrfReRanker 

pub struct RrfReRanker {
    pub k: f32,
}

Reciprocal-rank fusion. Combines multiple ranked result lists by summing 1 / (k + rank) across the lists for every document that appears in at least one.

Original paper: Cormack, Clarke & Büttcher (2009), “Reciprocal Rank Fusion outperforms Condorcet and individual Rank Learning Methods.”

Fields

k: f32

RRF smoothing constant. 60 is conventional.

Implementations

impl RrfReRanker

pub fn new(k: f32) -> Self

Construct with a custom k. Panics if k is non-finite or non-positive.

pub fn fuse<L, I>(&self, lists: L) -> Vec<Hit>

where L: IntoIterator<Item = I>, I: IntoIterator<Item = Hit>,

Fuse lists, each assumed sorted best-first. Returns hits sorted by descending fused score. Duplicate primary keys inside a single list are scored at their best (lowest) rank.

Trait Implementations

impl Clone for RrfReRanker

fn clone(&self) -> RrfReRanker

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for RrfReRanker

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

Formats the value using the given formatter.

impl Default for RrfReRanker

fn default() -> Self

Returns the “default value” for a type.

impl PartialEq for RrfReRanker

fn eq(&self, other: &RrfReRanker) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for RrfReRanker

impl StructuralPartialEq for RrfReRanker