Struct SignExpansionEncoder 

pub struct SignExpansionEncoder { /* private fields */ }

Encoder and decoder for surreal sign-expansion sequences.

The sign expansion of a surreal number x is a sequence of +/- signs obtained by walking the surreal tree from the root (0) to x:

• • means “x is to the right of the current node” (x > current)
• • means “x is to the left of the current node” (x < current)

Implementations

impl SignExpansionEncoder

pub fn new(signs: Vec<bool>) -> Self

Create an encoder for a given sign sequence.

pub fn from_fin_surreal(x: &FinSurreal) -> Self

Encode a dyadic rational as its sign expansion.

pub fn decode(&self) -> FinSurreal

Decode the sign sequence back to a dyadic rational approximation.

pub fn len(&self) -> usize

Return the length of the sign sequence (birthday of the surreal).

pub fn is_empty(&self) -> bool

True if the sign sequence is empty (represents zero).

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

Check if x ≤ y via the sign sequence lexicographic order.

In the surreal tree, x ≤ y iff the sign sequence of x is a prefix of or lexicographically ≤ the sign sequence of y (with + > -).

pub fn to_signs(&self) -> Vec<Sign>

Return the signs as a Vec for compatibility with FinSurreal.

Trait Implementations

impl Clone for SignExpansionEncoder

fn clone(&self) -> SignExpansionEncoder

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for SignExpansionEncoder

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

Formats the value using the given formatter.

impl Display for SignExpansionEncoder

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

Formats the value using the given formatter.