Struct HermitianLanczosOptions 

pub struct HermitianLanczosOptions {
    pub max_iter: usize,
    pub rtol: f64,
    pub atol: f64,
    pub breakdown_tol: f64,
    pub hermitian_tol: f64,
    pub verbose: bool,
}

Options for hermitian_lanczos_lowest_eigenpair.

These options control the maximum Krylov subspace dimension, convergence tolerance, and validation tolerance for the small projected Hermitian matrix. When in doubt, use Default::default.

Examples

use tensor4all_core::krylov::HermitianLanczosOptions;

let opts = HermitianLanczosOptions {
    max_iter: 32,
    rtol: 1.0e-9,
    ..HermitianLanczosOptions::default()
};
assert_eq!(opts.max_iter, 32);
assert_eq!(opts.rtol, 1.0e-9);

Fields

max_iter: usize

Maximum Krylov subspace dimension.

Larger values usually improve convergence but increase memory and the cost of the small Rayleigh-Ritz eigensolve. Default: 64.

rtol: f64

Relative residual tolerance.

Convergence requires ||A v - lambda v|| <= max(atol, rtol * max(1, |lambda|)). Default: 1e-10.

atol: f64

Absolute residual tolerance.

This is useful when targeting eigenvalues near zero. Default: 0.0.

breakdown_tol: f64

Breakdown threshold for the next Krylov vector norm.

If the orthogonalized vector norm is at or below this value, the current Krylov subspace is treated as invariant and iteration stops. Default: 1e-14.

hermitian_tol: f64

Hermitian validation tolerance for the projected Rayleigh-Ritz matrix.

The projected operator is rejected when V^dagger A V is not Hermitian within this absolute tolerance. Default: 1e-10.

verbose: bool

Whether to print per-iteration residual information.

Default: false.

Trait Implementations

impl Clone for HermitianLanczosOptions

fn clone(&self) -> HermitianLanczosOptions

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for HermitianLanczosOptions

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

Formats the value using the given formatter.

impl Default for HermitianLanczosOptions

fn default() -> Self

Returns the “default value” for a type.