Four Basic Linear Algebra Subprograms (BLAS) functions are shipped
with the
XL C/C++ compiler
in the
libxlopt library. The functions consist of
the following:
- sgemv (single-precision) and dgemv (double-precision),
which compute the matrix-vector product for a general matrix or its
transpose
- sgemm (single-precision) and dgemm (double-precision),
which perform combined matrix multiplication and addition for general
matrices or their transposes
Because the BLAS routines are written in Fortran, all parameters
are passed to them by reference, and all arrays are stored in column-major
order.
Note: Some error-handling code has been removed from the BLAS
functions in libxlopt, and no error messages are
emitted for calls to the these functions.
BLAS function syntax describes the
prototypes and parameters for the XL C/C++ BLAS
functions. The interfaces for these functions are similar to those
of the equivalent BLAS functions shipped in IBM's Engineering and
Scientific Subroutine Library (ESSL); for more information and examples
of usage of these functions, see Engineering and Scientific
Subroutine Library Guide and Reference, available at the Engineering and Scientific Subroutine
Library (ESSL) and Parallel ESSL Web page.
Linking the libxlopt library describes how to
link to the XL C/C++ libxlopt library
if you are also using a third-party BLAS library.