# POWEV: a subroutine package to evaluate eigenvalues and eigenvectors of large sparse matrices

## Description

Abstract We present here a FORTRAN subroutine package capable of evaluating the extreme (either largest or smallest) eigenvalues of a real symmetric matrix and its corresponding eigenvectors. The procedure employed is the well-known power method, in a new implementation which includes Chebyshev iterations to obtain faster convergence speed in certain cases, together with an auxiliary algorithm to automatically set the parameters of the Chebyshev iterations when there is no previous knowledge about the... Title of program: POWEV Catalogue Id: ACNR_v1_0 Nature of problem The numeric eigenvalue problem appears in a number of branches of Physics. Problems such as resolution of discrete systems with many degrees of freedom, exact diagonalization of quantum clusters, etc., require the calculation of eigenvalues and eigenvectors of large sparse matrices. Versions of this program held in the CPC repository in Mendeley Data ACNR_v1_0; POWEV; 10.1016/0010-4655(93)90040-J This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2019)