Related Experiment Video
Updated: Aug 14, 2025

Scalable Nanohelices for Predictive Studies and Enhanced 3D Visualization
Published on: November 12, 2014
Libkrylov: A modular open-source software library for extremely large on-the-fly matrix computations
Dmitrij Rappoport1, Samuel Bekoe1, Luke Nambi Mohanam1,2
1Department of Chemistry, University of California Irvine, Irvine, California, USA.
Abstract:
We present the design and implementation of libkrylov, an open-source library for solving matrix-free eigenvalue, linear, and shifted linear equations using Krylov subspace methods. The primary objectives of libkrylov are flexible API design and modular structure, which enables integration with specialized matrix-vector evaluation "engines." Libkrylov features pluggable preconditioning, orthonormalization, and tunable convergence control. Diagonal (conjugate gradient, CG), Davidson, and Jacobi-Davidson preconditioners are available, along with orthonormal and nonorthonormal (nKs) schemes. All functionality of libkrylov is exposed via Fortran and C application programming interfaces (APIs). We illustrate the performance of libkrylov for eigenvalue calculations arising in time-dependent density functional theory (TDDFT) in the Tamm-Dancoff approximation (TDA) and discuss the convergence behavior as a function of preconditioning and orthonormalization methods.
Related Concept Videos
One-Compartment Open Model: Wagner-Nelson and Loo Riegelman Method for ka Estimation
On...
Numerical Calculations
The solution to a problem is obtained using different methods. While manually solving algebraic symbols is one of the most common methods, the graphical method is often preferred. Computers...
Introduction to MATLAB
Vector Algebra: Method of Components
In many applications, the magnitudes and directions of...
Statically Indeterminate Problem Solving
Fast Decoupled and DC Powerflow

