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The ScaLAPACK library includes routines for the solution of linear
systems of equations, symmetric positive definite banded linear systems
of equations, condition estimation and iterative refinement, for LU and
Cholesky factorization, matrix inversion, full-rank linear least
squares problems, orthogonal and generalized orthogonal factorizations,
orthogonal transformation routines, reductions to upper Hessenberg,
bidiagonal and tridiagonal form, reduction of a symmetric-definite
generalized eigenproblem to standard form, the symmetric, generalized
symmetric and the nonsymmetric eigenproblem.
Software is available in single precision real, double precision real,
single precision complex, and double precision complex.
The subroutines in ScaLAPACK are classified as follows:
- driver routines, each of which solves a complete problem,
for example solving a system of linear equations, or computing the
eigenvalues of a real symmetric matrix.
Users are recommended to use a driver routine if there is one that
meets their requirements.
Global and local input error-checking are performed for these routines.
- computational routines, each of which performs a distinct
computational task, for example an LU factorization,
or the reduction of a real symmetric matrix to tridiagonal form.
Each driver routine calls a
sequence of computational routines. Users (especially software developers)
may need to call
computational routines directly to perform tasks, or sequences of tasks,
that cannot conveniently
be performed by the driver routines.
Global and local input error-checking are performed for these routines.
- auxiliary routines, which in turn can be classified as follows:
- routines that perform subtasks of block-partitioned algorithms -- in
particular, routines that implement unblocked versions of the algorithms;
- routines that perform some commonly required low-level
computations, for example scaling a matrix, computing a matrix-norm,
or generating an elementary Householder matrix; some of
these may be of interest to numerical analysts or software developers and
could be considered for future additions to the PBLAS;
- a few extensions to the PBLAS, such as routines for
matrix-vector operations involving complex symmetric
matrices (the PBLAS themselves are not strictly speaking part of ScaLAPACK).
A draft ScaLAPACK Users' Guide [32] and a comprehensive Installation
Guide is provided, as well as test suites for all ScaLAPACK, PBLAS, and BLACS
routines.
Next: Linear Equations
Up: ScaLAPACK: A Portable
Previous: LAPACK/ScaLAPACK code comparison
Susan Blackford
Thu Jul 25 15:38:00 EDT 1996