Struct Offset 

pub struct Offset<E: IntegerElement, BdIn: Bound, BdOut: Bound, C: Codec<E, BdIn>> { /* private fields */ }

d(c) - z: asymmetric quantization as a codec composition, not a feature.

A zero point is a codec, which is why the library needs no separate “asymmetric” mode and no branch for one (§1.3).

Decoding widens the alphabet: an inner value bounded by BdIn and a zero point of magnitude |z| produce a value bounded by BdIn + |z|. That is why the output bound is a separate parameter, and why Offset::new checks, once and in O(1), that the declared output bound covers the image and that no value overflows the element type. A None means no such codec exists — the same category as a non-conformant shape, decided before any arithmetic (C6).

Implementations

impl<E: IntegerElement, BdIn: Bound, BdOut: Bound, C: Codec<E, BdIn>> Offset<E, BdIn, BdOut, C>

pub fn new(inner: C, zero: E) -> Option<Self>

Compose inner with the zero point zero.

None when BdIn + |zero| exceeds the declared output bound or the element type’s own range, in which case the decode this describes does not land in the alphabet it claims to.

pub const fn zero(&self) -> E

The zero point.

Trait Implementations

impl<E: Clone + IntegerElement, BdIn: Clone + Bound, BdOut: Clone + Bound, C: Clone + Codec<E, BdIn>> Clone for Offset<E, BdIn, BdOut, C>

fn clone(&self) -> Offset<E, BdIn, BdOut, C>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<E, BdIn, BdOut, C> Codec<E, BdOut> for Offset<E, BdIn, BdOut, C>

where E: IntegerElement, BdIn: Bound, BdOut: Bound, C: Codec<E, BdIn>,

const MAX_BLOCK: usize = C::MAX_BLOCK

The most alphabet elements one code can produce.

const TIER: TierId = TierId::Offset

Which tier this is, for reports and for the kappa manifest.

const IS_FIXED_WIDTH: bool = C::IS_FIXED_WIDTH

Is decode_len always MAX_BLOCK?

type Code = <C as Codec<E, BdIn>>::Code

The stored code type.

fn decode_element(&self, code: Self::Code, i: usize) -> Alphabet<E, BdOut>

Decode element i of the block code names. Total for every i.

fn decode_len(&self, _code: Self::Code) -> usize

How many elements code actually produces.

fn decode_into(&self, code: Self::Code, out: &mut [Alphabet<E, Bd>]) -> usize

Decode one code, returning how many elements were written.

fn decode_seq(&self, codes: &[Self::Code], out: &mut [Alphabet<E, Bd>]) -> usize

Bulk path, returning how many elements were written in total.

impl<E: Copy + IntegerElement, BdIn: Copy + Bound, BdOut: Copy + Bound, C: Copy + Codec<E, BdIn>> Copy for Offset<E, BdIn, BdOut, C>

impl<E: Debug + IntegerElement, BdIn: Debug + Bound, BdOut: Debug + Bound, C: Debug + Codec<E, BdIn>> Debug for Offset<E, BdIn, BdOut, C>

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

Formats the value using the given formatter.

impl<E, BdIn, BdOut, C> Enumerable<E, BdOut> for Offset<E, BdIn, BdOut, C>

where E: IntegerElement, BdIn: Bound, BdOut: Bound, C: Enumerable<E, BdIn>,

const CODE_SPACE: usize = C::CODE_SPACE

The number of distinct codes.

fn code_at(index: usize) -> Self::Code

The index-th code. Total for index < CODE_SPACE.

fn index_of(code: Self::Code) -> usize

Where code sits in the enumeration.

fn as_index_stream(codes: &[Self::Code]) -> Option<IndexStream<'_>>

The stored code stream, read as the index stream it already is.

const SIGN_BIT_BOOK: bool = false

Whether the decoded book is the sign bit-decomposition: CODE_SPACE is a power of two and book[c][t] == 2 * bit(c, t) - 1 for every code c and every t below its log.