Struct sucds::bit_vectors::rank9sel::inner::Rank9SelIndex

pub struct Rank9SelIndex { /* private fields */ }

The index implementation of Rank9Sel separated from the bit vector.

Implementations

impl Rank9SelIndex

pub fn new(bv: &BitVector) -> Self

Creates a new vector from input bit vector bv.

pub fn select1_hints(self) -> Self

Builds an index for faster select1.

pub fn select0_hints(self) -> Self

Builds an index for faster select0.

pub fn num_ones(&self) -> usize

Gets the number of bits set.

pub fn num_zeros(&self) -> usize

Gets the number of bits unset.

pub unsafe fn rank1(&self, bv: &BitVector, pos: usize) -> Option<usize>

Returns the number of ones from the 0-th bit to the pos-1-th bit, or None if bv.len() < pos.

Arguments

• bv: Bit vector used in construction.
• pos: Bit position.

Complexity

• Constant

Safety

bv must be the one used in construction.

Examples

use sucds::bit_vectors::{BitVector, rank9sel::inner::Rank9SelIndex};

let bv = BitVector::from_bits([true, false, false, true]);
let idx = Rank9SelIndex::new(&bv);

unsafe {
    assert_eq!(idx.rank1(&bv, 1), Some(1));
    assert_eq!(idx.rank1(&bv, 2), Some(1));
    assert_eq!(idx.rank1(&bv, 3), Some(1));
    assert_eq!(idx.rank1(&bv, 4), Some(2));
    assert_eq!(idx.rank1(&bv, 5), None);
}

pub unsafe fn rank0(&self, bv: &BitVector, pos: usize) -> Option<usize>

Returns the number of zeros from the 0-th bit to the pos-1-th bit, or None if bv.len() < pos.

Arguments

• bv: Bit vector used in construction.
• pos: Bit position.

Complexity

• Constant

Safety

bv must be the one used in construction.

Examples

use sucds::bit_vectors::{BitVector, rank9sel::inner::Rank9SelIndex};

let bv = BitVector::from_bits([true, false, false, true]);
let idx = Rank9SelIndex::new(&bv);

unsafe {
    assert_eq!(idx.rank0(&bv, 1), Some(0));
    assert_eq!(idx.rank0(&bv, 2), Some(1));
    assert_eq!(idx.rank0(&bv, 3), Some(2));
    assert_eq!(idx.rank0(&bv, 4), Some(2));
    assert_eq!(idx.rank0(&bv, 5), None);
}

pub unsafe fn select1(&self, bv: &BitVector, k: usize) -> Option<usize>

Searches the position of the k-th bit set, or None if self.num_ones() <= k.

Arguments

• bv: Bit vector used in construction.
• k: Select query.

Complexity

• Logarithmic

Safety

bv must be the one used in construction.

Examples

use sucds::bit_vectors::{BitVector, rank9sel::inner::Rank9SelIndex};

let bv = BitVector::from_bits([true, false, false, true]);
let idx = Rank9SelIndex::new(&bv).select1_hints();

unsafe {
    assert_eq!(idx.select1(&bv, 0), Some(0));
    assert_eq!(idx.select1(&bv, 1), Some(3));
    assert_eq!(idx.select1(&bv, 2), None);
}

pub unsafe fn select0(&self, bv: &BitVector, k: usize) -> Option<usize>

Searches the position of the k-th bit unset, or None if self.num_zeros() <= k.

Arguments

• bv: Bit vector used in construction.
• k: Select query.

Complexity

• Logarithmic

Safety

bv must be the one used in construction.

Examples

use sucds::bit_vectors::{BitVector, rank9sel::inner::Rank9SelIndex};

let bv = BitVector::from_bits([true, false, false, true]);
let idx = Rank9SelIndex::new(&bv).select0_hints();

unsafe {
    assert_eq!(idx.select0(&bv, 0), Some(1));
    assert_eq!(idx.select0(&bv, 1), Some(2));
    assert_eq!(idx.select0(&bv, 2), None);
}

Trait Implementations

impl Clone for Rank9SelIndex

fn clone(&self) -> Rank9SelIndex

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Rank9SelIndex

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

Formats the value using the given formatter.

impl Default for Rank9SelIndex

fn default() -> Rank9SelIndex

Returns the “default value” for a type.

impl PartialEq for Rank9SelIndex

fn eq(&self, other: &Rank9SelIndex) -> bool

This method tests for self and other values to be equal, and is used by ==.

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

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

impl Serializable for Rank9SelIndex

fn serialize_into<W: Write>(&self, writer: W) -> Result<usize>

Serializes the data structure into the writer, returning the number of serialized bytes.

fn deserialize_from<R: Read>(reader: R) -> Result<Self>

Deserializes the data structure from the reader.

fn size_in_bytes(&self) -> usize

Returns the number of bytes to serialize the data structure.

fn size_of() -> Option<usize>

Returns the size of a primitive type in bytes (if the type is so).

impl Eq for Rank9SelIndex

impl StructuralEq for Rank9SelIndex

impl StructuralPartialEq for Rank9SelIndex