What you need to know to use vector subprograms

What you need to know to use vector subprograms

The following sections describe overall considerations for using vector subprograms:

•BLAS storage conventions

❏Fortran storage of arrays

❏Fortran array argument association

•BLAS indexing conventions

❏Forward storage

❏Backward storage

❏Increment arguments

•Operator arguments in the BLAS Standard

•Representation of a permutation matrix

•Representation of a Householder matrix

BLAS storage conventions

The Basic Linear Algebra Subprograms (BLAS) were developed to enhance the portability of published linear algebra codes. In particular LAPACK, the high-level public-domain linear equation package, uses the BLAS. When your routines use the VECLIB BLAS, you increase the efficiency of those routines on your Hewlett-Packard servers.

You need not limit your use of the VECLIB BLAS to linear algebra codes. Because these subprograms are portable, modular, and efficient, you can incorporate them into your programs. To realize the full power of the BLAS, you should understand storage and indexing conventions.

Chapter 2 Basic Vector Operations 33