LAPACK is a library of Fortran 77 subroutines for solving the most commonly occurring problems in numerical linear algebra. It is freely-available software, and is copyrighted. LAPACK is available on netlib and can be obtained via the World Wide Web and anonymous ftp. http://www.netlib.org/lapack/ The complete package, including test code and timing programs in four different Fortran data types (real, complex, double precision, double complex), contains some 805,000 lines of Fortran source and comments. You will need approximately 33 Mbytes to read the complete tape. We recommend that you run the testing and timing programs. A README file containing the information in this letter is located in the LAPACK directory. Postscript and LaTeX versions of the Quick Installation Guide are in the LAPACK/INSTALL directory, in the files lawn81.tex, psfig.tex, lawn81.ps, and org2.ps. Consult the Installation Guide for further details on installing the package and on what is contained in each subdirectory. For complete information on the LAPACK Testing and Timing Suites please consult LAPACK Working Note 41 "Installation Guide for LAPACK". To view an HTML version of the Users' Guide please refer to the URL http://www.netlib.org/lapack/lug/lapack_lug.html. The Fortran90 interface to LAPACK is available, as well as an f2c'ed version of LAPACK, and a C++ version of a subset of LAPACK routines. Refer to the following URLs on netlib for further information: http://www.netlib.org/lapack90/ http://www.netlib.org/clapack/ http://www.netlib.org/lapack++/ http://www.cs.utk.edu/java/f2j/ Or, for more information on the distributed-memory version of LAPACK, consult the ScaLAPACK index on netlib: http://www.netlib.org/scalapack/ WWW: http://www.netlib.org/lapack/