Enum DecodeRule 

pub enum DecodeRule {
    SumProduct,
    MinSum,
    ScaledMinSum(f32),
}

The check-node update rule for Ldpc::decode_soft_with.

SumProduct is the exact belief-propagation rule (2·atanh(∏ tanh(msg/2))) and the default everywhere — on-air decode uses it unless a caller explicitly opts into a min-sum variant. The min-sum rules approximate the check-node update by its dominant term (∏sign · min|msg|), trading a small coding-gain loss for a cheaper, transcendental-free update; ScaledMinSum attenuates the min-sum message by a factor (~0.75–0.8 recovers most of the gap). This enum exists to measure that trade (see the snr::ldpc_decode_rule sweep and the throughput::fec LDPC benchmarks); it is not wired into the frame layer.

Variants

SumProduct

Exact sum-product (tanh product rule). The default.

MinSum

Min-sum approximation: ext = ∏sign(other) · min|other|.

ScaledMinSum(f32)

Scaled (attenuated) min-sum: min-sum message multiplied by this factor.

Trait Implementations

impl Clone for DecodeRule

fn clone(&self) -> DecodeRule

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for DecodeRule

impl Debug for DecodeRule

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

Formats the value using the given formatter.

impl PartialEq for DecodeRule

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for DecodeRule