LAPACK is a linear algebra library for high-performance computers. The library includes Fortran 77 subroutines for the analysis and solution of systems of simultaneous linear algebraic equations, linear least-squares problems, and matrix eigenvalue problems. Our approach to achieving high efficiency is based on the use of a standard set of Basic Linear Algebra Subprograms (the BLAS), which can be optimized for each computing environment. By confining most of the computational work to the BLAS, the subroutines should be transportable and efficient across a wide range of computers.

This working note describes how to install, test, and time this release of LAPACK.

The instructions for installing, testing, and timing are designed for a person whose responsibility is the maintenance of a mathematical software library. We assume the installer has experience in compiling and running Fortran programs and in creating object libraries. The installation process involves untarring the file, creating a set of libraries, and compiling and running the test and timing programs.

This guide combines the instructions for the Unix and non-Unix installations of LAPACK (the Windows 98/NT PC installation is described in Appendix E, and the VAX installation is described in Appendix F). At this time, the VAX installation of LAPACK can only be obtained after first untarring the Unix tar file and then following the instructions in Appendix F.

Section 3 describes how the files are organized in the file, and Section 4 gives a general overview of the parts of the test package. Step-by-step instructions appear in Section 5 for the Unix version and in the appendices for Windows 98/NT and VAX-type installations.

For users desiring additional information, Sections 7 and 8 give details of the test and timing programs and their input files. Appendices A and B briefly describe the LAPACK routines and auxiliary routines provided in this release. Appendix C lists the operation counts we have computed for the BLAS and for some of the LAPACK routines. Appendix D, entitled ``Caveats'', is a compendium of the known problems from our own experiences, with suggestions on how to overcome them.

**It is strongly advised that the user read Appendix
D before proceeding with the installation process.**

Appendices E and F contain the instructions to install LAPACK on a non-Unix system.