Struct LogMessage 

pub struct LogMessage {
    pub variable: String,
    pub log_values: Array1<f64>,
}

A message stored in log-space for numerical stability.

All arithmetic (product, damping) is performed in log space, then converted back to probability space only when computing beliefs.

Fields

variable: String

Variable this message is “about”

log_values: Array1<f64>

Log-probabilities (not necessarily normalised)

Implementations

impl LogMessage

pub fn from_factor_slice(variable: &str, values: &ArrayD<f64>) -> Self

Create from a (probability-space) crate::Factor projected onto a single variable.

pub fn uniform(variable: &str, card: usize) -> Self

Create a uniform log-message of length card.

pub fn log_normalise(&mut self)

Log-sum-exp normalise (subtract max, then subtract log-sum-exp).

pub fn to_probs(&self) -> Array1<f64>

Convert to probability-space Array1.

pub fn residual_linf(&self, other: &LogMessage) -> f64

L∞ residual vs another message (in log space).

pub fn damp(&self, old: &LogMessage, lambda: f64) -> Self

Apply damping: λ * self + (1-λ) * old (in log space via log-sum-exp).

Trait Implementations

impl Clone for LogMessage

fn clone(&self) -> LogMessage

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for LogMessage

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

Formats the value using the given formatter.