Enum CGBetaFormula 

pub enum CGBetaFormula {
    FletcherReeves,
    PolakRibiere,
    HestenesStiefel,
}

Beta computation formula for Conjugate Gradient.

Different formulas provide different convergence properties and numerical stability characteristics.

Variants

FletcherReeves

Fletcher-Reeves: β = (g_{k+1}^T g_{k+1}) / (g_k^T g_k)

Most stable but can be slow on non-quadratic problems.

PolakRibiere

Polak-Ribière: β = g_{k+1}^T (g_{k+1} - g_k) / (g_k^T g_k)

Better performance than FR, includes automatic restart (β < 0).

HestenesStiefel

Hestenes-Stiefel: β = g_{k+1}^T (g_{k+1} - g_k) / (d_k^T (g_{k+1} - g_k))

Similar to PR but with different denominator, can be more robust.

Trait Implementations

impl Clone for CGBetaFormula

fn clone(&self) -> CGBetaFormula

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for CGBetaFormula

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

Formats the value using the given formatter.

impl PartialEq for CGBetaFormula

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for CGBetaFormula

impl Eq for CGBetaFormula

impl StructuralPartialEq for CGBetaFormula