solvers(3F)

NAME
     SOLVERS - SGI developed linear equations solvers.

DESCRIPTION
     Two direct solvers for sparse linear systems of equations are available
     in complib.sgimath, PSLDLT and PSLDU. These solvers are optimized and
     parallelized for the SGI platforms. For direct solvers for dense linear
     systems of equations, see LAPACK manpage.

     PSLDLT solves sparse symmetric linear systems of the form
        Ax = b
     where A is an n x n symmetric input matrix, b is an input vector of
     length n, and x is an unknown vector of length n.  PSLDLT uses a direct
     method: A is factored into the form
       A = L D L-transpose
     where L is a lower triangular matrix with unit diagonal and D is a
     diagonal matrix.
     This routine is double precision only and is available in the mp versions
     of complib.sgimath.
     See the manpage for PSLDLT for details.


     PSLDU solves sparse unsymmetric linear systems of the form
        Ax = b
     where A is an n x n input matrix with symmetric non-zero pattern but
     unsymmetric non-zero values, b is an input vector of length n, and x is
     an unknown vector of length n.  PSLDU uses a direct method: A is factored
     into the form
       A = L D U
     where L is a lower triangular matrix with unit diagonal, D is a diagonal
     matrix and U is an upper triangular matrix with unit diagonal.
     See the manpage for PSLDU for details.