Struct LanczosParams 

pub struct LanczosParams {
    pub basis_size: Option<usize>,
    pub max_restarts: usize,
    pub tol: f64,
}

Parameters for the restarted Lanczos eigensolver.

Fields

basis_size: Option<usize>

Krylov basis vectors held at once. None derives it from the requested component count as max(2k + 10, k + 20), which leaves enough room above the wanted pairs for the restart to make progress.

max_restarts: usize

Maximum restart cycles. Each cycle costs one basis worth of matrix-vector products plus the orthogonalisation against the basis, so this is the only knob that bounds the run time.

tol: f64

Relative residual tolerance. A Ritz pair counts as converged once ||A x - lambda x|| drops below tol * ||A||. The scaling matters: an absolute threshold is unreachable for a matrix whose norm is large and trivially met for one whose norm is tiny.

Implementations

impl LanczosParams

pub fn new() -> LanczosParams

Defaults tuned on a single cell diffusion kernel.

Returns

Self with a derived basis size, 64 restarts and a relative tolerance of 1e-8.

Trait Implementations

impl Clone for LanczosParams

fn clone(&self) -> LanczosParams

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for LanczosParams

impl Debug for LanczosParams

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

Formats the value using the given formatter.

impl Default for LanczosParams

fn default() -> LanczosParams

Returns the “default value” for a type.