Class Scine::Utils::PreconditionerEvaluator

class PreconditionerEvaluator

Interface for the preconditioner evaluators in the Davidson iterative diagonalizer.

Subclassed by Scine::Utils::IndirectPreconditionerEvaluator

Public Functions

virtual Eigen::VectorXd evaluate(double eigenvalue) const = 0

Evaluates the preconditioner vector.

The preconditioner elements are p_k = (H - h_k*I)^{-1}, where H is the exact or approximated matrix to diagonalize. For diagonally dominant matrices H can be approximated with D, the diagonal of H.