Struct RankSupport 

pub struct RankSupport { /* private fields */ }

Rank support structure for plain bitvectors.

The structure depends on the parent bitvector and assumes that the parent remains unchanged. Using the BitVector interface is usually more convenient.

Implementations

impl RankSupport

pub const BLOCK_SIZE: usize = 512usize

Number of bits per block (512).

pub fn blocks(&self) -> usize

Returns the number of 512-bit blocks in the bitvector.

pub fn new(parent: &BitVector) -> RankSupport

Builds a rank support structure for the parent bitvector.

Examples

use simple_sds_sbwt::bit_vector::BitVector;
use simple_sds_sbwt::bit_vector::rank_support::RankSupport;

let data = vec![false, true, true, false, true, false, true, true, false, false, false];
let bv: BitVector = data.into_iter().collect();
let rs = RankSupport::new(&bv);
assert_eq!(rs.blocks(), 1);

pub fn rank(&self, parent: &BitVector, index: usize) -> usize

Returns the rank at the specified index of the bitvector.

Arguments

• parent: The parent bitvector.
• index: Index in the bit array or value in the integer array.

Examples

use simple_sds_sbwt::bit_vector::BitVector;
use simple_sds_sbwt::bit_vector::rank_support::RankSupport;

let data = vec![false, true, true, false, true, false, true, true, false, false, false];
let bv: BitVector = data.into_iter().collect();
let rs = RankSupport::new(&bv);
assert_eq!(rs.rank(&bv, 0), 0);
assert_eq!(rs.rank(&bv, 1), 0);
assert_eq!(rs.rank(&bv, 2), 1);
assert_eq!(rs.rank(&bv, 7), 4);

Panics

May panic if index >= parent.len().

pub unsafe fn rank_unchecked(&self, parent: &BitVector, index: usize) -> usize

Unsafe version of RankSupport::rank without bounds checks.

Safety

Behavior is undefined if index >= parent.len().

Trait Implementations

impl Clone for RankSupport

fn clone(&self) -> RankSupport

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for RankSupport

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

Formats the value using the given formatter.

impl PartialEq for RankSupport

fn eq(&self, other: &RankSupport) -> 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 Serialize for RankSupport

fn serialize_header<T: Write>(&self, writer: &mut T) -> Result<()>

Serializes the header to the writer.

fn serialize_body<T: Write>(&self, writer: &mut T) -> Result<()>

Serializes the body to the writer.

fn load<T: Read>(reader: &mut T) -> Result<Self>

Loads the struct from the reader.

fn size_in_elements(&self) -> usize

Returns the size of the serialized struct in u64 elements.

fn serialize<T: Write>(&self, writer: &mut T) -> Result<()>

Serializes the struct to the writer.

fn size_in_bytes(&self) -> usize

Returns the size of the serialized struct in bytes.

impl Eq for RankSupport

impl StructuralPartialEq for RankSupport