TOMS384
Eigenvalues and Eigenvectors of a Real Symmetric Matrix

TOMS384 is a FORTRAN77 library which implements ACM TOMS algorithm 384, for computing the eigenvalues and eigenvectors of a symmetric matrix.

The text of many ACM TOMS algorithms is available online through ACM: http://www.acm.org/pubs/calgo or NETLIB: http://www.netlib.org/toms/index.html.

Languages:

TOMS384 is available in a FORTRAN77 version.

Related Data and Programs:

EISPACK, a FORTRAN90 library which can compute eigenvalues and eigenvectors of a variety of matrix types.

LAPACK_EXAMPLES, a FORTRAN90 program which demonstrates the use of the LAPACK linear algebra library.

TEST_MAT, a FORTRAN90 library which defines matrices with various properties for testing linear algebra software.

Reference:

1. Pete Stewart,
   Algorithm 384: Eigenvalues and Eigenvectors of a Real Symmetric Matrix,
   Communications of the ACM,
   June 1970, Volume 13, Number 6, pages 369-371.
2. Pete Stewart,
   Incorporating Origin Shifts into the Symmetric QR Algorithm for Symmetric Tridiagonal Matrices,
   Communications of the ACM,
   June 1970, Volume 13, Number 6, pages 365-367.

Source Code:

• toms384.f, the source code.
• toms384.sh, commands to compile the source code.

Examples and Tests:

• toms384_prb.f, a sample calling program.
• toms384_prb.sh, commands to compile and run the sample program.
• toms384_prb_output.txt, the output file.

List of Routines:

• SYMQR computes the eigenvalues and eigenvectors of a symmetric matrix.
• SINCOS computes a plane rotation.

You can go up one level to the FORTRAN77 source codes.