Struct BitVec2048 

pub struct BitVec2048 { /* private fields */ }

A 2048-bit bitvector.

The vector is stored as 32 little-endian 64-bit words. Bit n resides in word n / 64, at position n % 64.

Implementations

impl BitVec2048

pub fn new() -> Self

Create a new all-zero bitvector.

pub fn set(&mut self, bit: usize)

Set bit bit to 1.

Panics

Panics if bit >= 2048.

pub fn get(&self, bit: usize) -> bool

Return the value of bit bit.

Panics

Panics if bit >= 2048.

pub fn popcount(&self) -> u32

Count the number of bits set to 1 (popcount / Hamming weight).

pub fn and(&self, other: &Self) -> Self

Bitwise AND of two bitvectors.

pub fn or(&self, other: &Self) -> Self

Bitwise OR of two bitvectors.

pub fn intersection_popcount(&self, other: &Self) -> u32

Count the number of bits set in A & B without allocating a temporary.

This is the fundamental primitive for bulk Tanimoto computation: hoisting the query popcount and reusing this per db entry avoids the per-pair allocation of self.and(other).popcount().

pub fn tanimoto_with_counts( &self, other: &Self, self_popcount: u32, other_popcount: u32, ) -> f32

Tanimoto similarity given precomputed popcounts, returning f32.

Use when calling one query against many db entries: hoist self_popcount = query.popcount() outside the loop, compute other_popcount = db_entry.popcount() once per entry, then call this instead of tanimoto() to avoid redundant allocation and recomputation.

Returns 1.0 when union is zero (both all-zero convention).

pub fn tanimoto(&self, other: &Self) -> f64

Tanimoto similarity: |A & B| / |A | B|.

Returns 1.0 when both vectors are all-zero (the empty-set convention).

pub fn dice(&self, other: &Self) -> f64

Dice similarity: 2|A & B| / (|A| + |B|).

Returns 1.0 when both vectors are all-zero.

pub fn fold(&self, bits: usize) -> Self

XOR-fold this 2048-bit vector to bits bits.

The upper half is XOR-folded into the lower half, and the upper half is zeroed. This is applied recursively until the target width is reached.

bits must be 1024, 512, or 256.

Panics

Panics if bits is not one of 1024, 512, or 256.

pub fn to_bitvecn(&self) -> BitVecN

Convert to a variable-length BitVecN with the same bits.

Trait Implementations

impl Clone for BitVec2048

fn clone(&self) -> BitVec2048

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for BitVec2048

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

Formats the value using the given formatter.

impl Default for BitVec2048

fn default() -> Self

Returns the “default value” for a type.

impl Eq for BitVec2048

impl PartialEq for BitVec2048

fn eq(&self, other: &BitVec2048) -> 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 StructuralPartialEq for BitVec2048