ARPACK
Eigenvalues and Eigenvectors of Large Matrices

ARPACK is a library of MATLAB routines which can compute eigenvalues and eigenvectors of large matrices. The ARPACK library is accessible in MATLAB via the EIGS command.

1. help eigs
   will print out information about how to use the EIGS command inside of MATLAB to interface with ARPACK.
2. Information about the use of the ARPACK execution trace facilities available through "debug.h" is given in arpack_debug.txt
3. Information about the use of the ARPACK operation count and timing statistics available through "stat.h" is given in arpack_stat.txt

Related Data and Programs:

ARPACK is also available in a FORTRAN90 version.

EISPACK is a FORTRAN90 library of eigenvalue routines.

LAPACK is a FORTRAN90 library of modern eigenvalue routines.

TEST_EIGEN is a library of FORTRAN90 routines that define various eigenvalue test cases.

TEST_MAT is a library of FORTRAN90 routines that define various test matrices.

Reference:

1. Richard Lehoucq, Danny Sorensen, Chao Yang,
   ARPACK User's Guide:
   Solution of Large Scale Eigenvalue Problems with Implicitly Restarted Arnoldi Methods,
   available as a PDF file
2. Danny Sorensen,
   Implicitly Restarted Arnoldi/Lanczos Methods for Large Scale Eigenvalue Calculations,
   available as a PDF file

Examples and Tests:

• arpack_test.m, a script that runs all the tests.
• arpack_test.out, output of the tests.
• arpack_test01.m, tests EIGS for smallest and largest eigenvalues, with the matrix supplied explicitly.
• arpack_test02.m, tests EIGS for smallest eigenvalues, with the matrix supplied implicitly, by a routine which computes inverse(A)*x.
• ainv_x.m, computes inverse(A)*x for problem 2.
• timestamp.m, prints the current YMDHMS date as a timestamp.

You can go up one level to the MATLAB source codes.