Struct LogSemiring 

pub struct LogSemiring(/* private fields */);

A log-space semiring element.

Values are natural logarithms of non-negative weights. Semiring addition is stable log-sum-exp, multiplication is addition in log space, -inf is zero, and 0 is one. NaN is rejected at construction because it cannot satisfy the algebraic contract.

Implementations

impl LogSemiring

pub fn from_log(value: f64) -> Option<Self>

Construct from a log-space value. Returns None for NaN.

pub fn from_weight(weight: f64) -> Option<Self>

Construct from a non-negative linear-space weight.

pub fn log_value(self) -> f64

Return the stored natural logarithm.

pub fn weight(self) -> f64

Return the represented linear-space weight.

Trait Implementations

impl Clone for LogSemiring

fn clone(&self) -> LogSemiring

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for LogSemiring

impl Debug for LogSemiring

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

Formats the value using the given formatter.

impl PartialEq for LogSemiring

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

Equality operator ==.

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

Inequality operator !=.

impl Semiring for LogSemiring

fn zero() -> Self

Additive identity.

fn one() -> Self

Multiplicative identity.

fn plus(&self, other: &Self) -> Self

Semiring addition.

fn times(&self, other: &Self) -> Self

Semiring multiplication.

fn is_zero(&self) -> bool

Whether this value is the additive identity and therefore outside the relation’s support.

impl StructuralPartialEq for LogSemiring