Struct OptimizationState_blend 

pub struct OptimizationState_blend {
    pub geom_history: VecDeque<DVector<f64>>,
    pub true_hess_history: VecDeque<DMatrix<f64>>,
    pub grad_history: VecDeque<DVector<f64>>,
    pub f_vec_history: VecDeque<DVector<f64>>,
    pub e1_history: VecDeque<f64>,
    pub energy_history: VecDeque<f64>,
    pub max_history: usize,
    pub prev_e1: Option<f64>,
    pub trust_radius: f64,
}

Holds optimization state for the GDIIS_blend and GEDIIS_blend implementations.

Key Difference from OptimizationState

The existing OptimizationState stores INVERSE Hessians in hess_history. This struct stores TRUE Hessians in true_hess_history, matching the convention where Hm = mean(Hhist) and Hm^{-1} is computed by inversion.

Note on naming

The name _blend suffix distinguishes this from the existing OptimizationState and indicates that it is designed for the GDIIS_blend (inverted mean Hessian error vectors) and GEDIIS_blend (Taylor expansion B-matrix) methods.

Fields

geom_history: VecDeque<DVector<f64>>

History of geometries as column vectors.

true_hess_history: VecDeque<DMatrix<f64>>

History of TRUE Hessian matrices (NxN), NOT inverse Hessians.

Hhist/Bhist (list of NxN matrices). Mean is inverted for error vectors: error_i = H_mean^{-1} @ F_i.

grad_history: VecDeque<DVector<f64>>

History of MECP g-vectors (perpendicular component) in Ha/A.

f_vec_history: VecDeque<DVector<f64>>

History of f-vectors (energy difference drive term) in Hartree (Ha).

e1_history: VecDeque<f64>

History of E1 energies (used as RHS for EDIIS: y = [-E_hist, 1]).

energy_history: VecDeque<f64>

History of E1 - E2 energy differences (stored for compatibility / debugging but NOT used in EDIIS RHS).

max_history: usize

Maximum number of history entries (keeps max 4).

prev_e1: Option<f64>

E1 energy from the previous iteration (for trust-radius adjustment).

trust_radius: f64

Current trust radius for adaptive step control. Initialized from config.max_step_size and adjusted dynamically.

Implementations

impl OptimizationState_blend

pub fn new(max_history: usize, trust_radius: f64) -> Self

Creates a new empty optimization state for blend methods.

pub fn has_enough_history(&self) -> bool

Returns true when at least 3 iterations of history exist, matching the minimum needed for reliable DIIS interpolation.

pub fn add_to_history( &mut self, geom: DVector<f64>, grad: DVector<f64>, f_vec: DVector<f64>, true_hess: DMatrix<f64>, e1: f64, energy_diff: f64, )

Adds a new entry to all history deques with FIFO eviction.

Trait Implementations

impl Clone for OptimizationState_blend

fn clone(&self) -> OptimizationState_blend

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for OptimizationState_blend

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

Formats the value using the given formatter.