Struct Coded 

pub struct Coded {
    pub norm: f32,
    pub scale: f32,
    pub lo: f32,
    pub delta: f32,
}

What a code needs alongside it to be measured against a query.

lo and delta are only worth storing for Bits::Four. At one bit they are the same two numbers for every vector in the collection, so a store that keeps them per vector is keeping the dimension eight bytes at a time.

Fields

norm: f32

The length of the vector minus its centroid.

scale: f32

One over the cosine between the vector and what its code reconstructs to. That cosine is the estimator’s correction and the whole of RaBitQ over plain binary quantisation.

Stored the wrong way up on purpose, because the estimator divides by it exactly once per member and a float division was 44 percent of what a member cost: 3.56 nanoseconds became 1.98 at 128 dimensions when the division became a multiplication. Nothing else here reads it, so nothing else pays for the inversion.

lo: f32

The value level zero reconstructs to, over the length of the reconstruction.

delta: f32

What one level is worth, over the length of the reconstruction.

Trait Implementations

impl Clone for Coded

fn clone(&self) -> Coded

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for Coded

impl Debug for Coded

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

Formats the value using the given formatter.

impl PartialEq for Coded

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for Coded