BLAS1_S
Basic Linear Algebra Subprograms
Level 1
Single Precision Real Arithmetic

BLAS1_S is a C library which implements the Level 1 BLAS, or Basic Linear Algebra Subprograms.

The BLAS are a small core library of linear algebra utilities, which can be highly optimized for various architectures. Software that relies on the BLAS is thus highly portable, and will typically run very efficiently.

The Level 1 BLAS are primarily for use in vector operations. In certain cases, they may also be used to operate on the rows or columns of a two-dimensional array.

Licensing:

The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.

Languages:

BLAS1_S is available in a C version and a C++ version and a FORTRAN90 version and a MATLAB version.

Related Data and Programs:

BLAS0, a C library which contains auxilliary functions for the Basic Linear Algebra Subprograms (BLAS).

BLAS1_C, a C library which contains basic linear algebra routines for vector-vector operations, using single precision complex arithmetic.

BLAS1_D, a C library which contains basic linear algebra routines for vector-vector operations, using double precision real arithmetic.

BLAS1_Z, a C library which contains basic linear algebra routines for vector-vector operations, using double precision complex arithmetic.

BLAS2, a C library which contains basic linear algebra subprograms (BLAS) for matrix-vector operations;

BLAS3, a C library which contains basic linear algebra subprograms (BLAS) for matrix-matrix operations;

CLAPACK, C programs which illustrate the use of the CLAPACK library, a translation of the FORTRAN77 BLAS and LAPACK linear algebra libraries, including single and double precision, real and complex arithmetic.

LINPACK, a C library which solves linear systems using single precision real arithmetic;

SUPER_BLAS, a C library which implements some of the Basic Linear Algebra Subprograms for fast execution.

Author:

Original FORTRAN77 version by Charles Lawson, Richard Hanson, David Kincaid, Fred Krogh. C version by John Burkardt.

Reference:

1. Thomas Coleman, Charles vanLoan,
   Handbook for Matrix Computations,
   SIAM, 1988,
   ISBN13: 978-0-898712-27-8,
   LC: QA188.C65.
2. Jack Dongarra, Jim Bunch, Cleve Moler, Pete Stewart,
   LINPACK User's Guide,
   SIAM, 1979,
   ISBN13: 978-0-898711-72-1,
   LC: QA214.L56.
3. Charles Lawson, Richard Hanson, David Kincaid, Fred Krogh,
   Algorithm 539: Basic Linear Algebra Subprograms for Fortran Usage,
   ACM Transactions on Mathematical Software,
   Volume 5, Number 3, September 1979, pages 308-323.

Source Code:

• blas1_s.c, the level 1 BLAS in single precision real arithmetic.
• blas1_s.h, an include file for BLAS1_S.

Examples and Tests:

• blas1_s_test.c, the calling program.
• blas1_s_test.txt the resulting output file.

List of Routines:

• I4_MAX returns the maximum of two integers.
• I4_MIN returns the smaller of two integers.
• ISAMAX finds the index of the float vector element of maximum absolute value.
• LSAME returns TRUE if CA is the same letter as CB regardless of case.
• R4_ABS returns the absolute value of a float.
• R4_MAX returns the maximum of two floats.
• R4_SIGN returns the sign of a float.
• SASUM takes the sum of the absolute values of a float vector.
• SAXPY computes float constant times a vector plus a vector.
• SCOPY copies a float vector X to a vector Y.
• SDOT forms the dot product of two float vectors.
• SMACH computes machine parameters of float arithmetic.
• SNRM2 returns the euclidean norm of a float vector.
• SROT applies a float plane rotation.
• SROTG constructs a float Givens plane rotation.
• SSCAL scales a float vector by a constant.
• SSWAP interchanges two float vectors.
• XERBLA is an error handler for the LAPACK routines.

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