Struct BitMask 

pub struct BitMask { /* private fields */ }

A compact, word-aligned bitmask over nrows rows.

Words are u64, stored LSB-first within each word. Bit i is set in words[i / 64] at position i % 64. Tail bits (above nrows) are guaranteed to be zero so that iteration never yields phantom rows.

Implementations

impl BitMask

pub fn all_true(nrows: usize) -> Self

Construct a mask covering all nrows rows (all-true).

pub fn all_false(nrows: usize) -> Self

Construct a mask where no rows are set (all-false).

pub fn from_bools(bools: &[bool]) -> Self

Construct from a Vec<bool>, one entry per row.

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

Get bit at row i.

pub fn count_ones(&self) -> usize

Number of set bits (masked-in rows).

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

Merge two masks with AND semantics (chain of filter().filter()).

Panics if nrows differs – this is a programming error (same base df).

pub fn iter_set(&self) -> impl Iterator<Item = usize> + '_

Iterate over set row indices in ascending order (deterministic).

pub fn nrows(&self) -> usize

Returns the total number of rows this mask covers.

pub fn nwords(&self) -> usize

Number of backing u64 words (= ceil(nrows / 64)).

pub fn words_slice(&self) -> &[u64]

Read-only access to the backing words. Used by AdaptiveSelection to perform AND/OR over raw words without re-iterating bit-by-bit.

pub fn from_words_for_test(words: Vec<u64>, nrows: usize) -> Self

Construct a BitMask directly from owned words and a row count.

The caller must ensure tail bits past nrows are zero. Used by AdaptiveSelection::intersect/union after the AND/OR step.

Trait Implementations

impl Clone for BitMask

fn clone(&self) -> BitMask

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for BitMask

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

Formats the value using the given formatter.

impl PartialEq for BitMask

fn eq(&self, other: &BitMask) -> 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 Eq for BitMask

impl StructuralPartialEq for BitMask