Enum DistanceMetric 

#[non_exhaustive]
pub enum DistanceMetric {
    Cosine,
    L2,
    InnerProduct,
}

Distance metric used for vector similarity. Mirrors pgvector’s own taxonomy 1:1 — operators familiar with <=> / <-> / <#> pick the metric they would have picked there.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Cosine

Cosine similarity (<=> operator). The right default for normalized embeddings (text-embedding-3-*, etc.).

L2

Euclidean / L2 distance (<-> operator).

InnerProduct

Inner product (<#> operator). Note: pgvector’s <#> returns the negative inner product so smaller is “more similar”; the store inverts it on read so caller-facing scores stay “higher = better”.

Trait Implementations

impl Clone for DistanceMetric

fn clone(&self) -> DistanceMetric

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for DistanceMetric

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

Formats the value using the given formatter.

impl Default for DistanceMetric

fn default() -> DistanceMetric

Returns the “default value” for a type.

impl PartialEq for DistanceMetric

fn eq(&self, other: &DistanceMetric) -> 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 DistanceMetric

impl Eq for DistanceMetric

impl StructuralPartialEq for DistanceMetric