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zlaqsy.f(3)                         LAPACK                         zlaqsy.f(3)

NAME
       zlaqsy.f -

SYNOPSIS
   Functions/Subroutines
       subroutine zlaqsy (UPLO, N, A, LDA, S, SCOND, AMAX, EQUED)
           ZLAQSY scales a symmetric/Hermitian matrix, using scaling factors
           computed by spoequ.

Function/Subroutine Documentation
   subroutine zlaqsy (characterUPLO, integerN, complex*16, dimension( lda, *
       )A, integerLDA, double precision, dimension( * )S, double
       precisionSCOND, double precisionAMAX, characterEQUED)
       ZLAQSY scales a symmetric/Hermitian matrix, using scaling factors
       computed by spoequ.

       Purpose:

            ZLAQSY equilibrates a symmetric matrix A using the scaling factors
            in the vector S.

       Parameters:
           UPLO

                     UPLO is CHARACTER*1
                     Specifies whether the upper or lower triangular part of the
                     symmetric matrix A is stored.
                     = 'U':  Upper triangular
                     = 'L':  Lower triangular

           N

                     N is INTEGER
                     The order of the matrix A.  N >= 0.

           A

                     A is COMPLEX*16 array, dimension (LDA,N)
                     On entry, the symmetric matrix A.  If UPLO = 'U', the leading
                     n by n upper triangular part of A contains the upper
                     triangular part of the matrix A, and the strictly lower
                     triangular part of A is not referenced.  If UPLO = 'L', the
                     leading n by n lower triangular part of A contains the lower
                     triangular part of the matrix A, and the strictly upper
                     triangular part of A is not referenced.

                     On exit, if EQUED = 'Y', the equilibrated matrix:
                     diag(S) * A * diag(S).

           LDA

                     LDA is INTEGER
                     The leading dimension of the array A.  LDA >= max(N,1).

           S

                     S is DOUBLE PRECISION array, dimension (N)
                     The scale factors for A.

           SCOND

                     SCOND is DOUBLE PRECISION
                     Ratio of the smallest S(i) to the largest S(i).

           AMAX

                     AMAX is DOUBLE PRECISION
                     Absolute value of largest matrix entry.

           EQUED

                     EQUED is CHARACTER*1
                     Specifies whether or not equilibration was done.
                     = 'N':  No equilibration.
                     = 'Y':  Equilibration was done, i.e., A has been replaced by
                             diag(S) * A * diag(S).

       Internal Parameters:

             THRESH is a threshold value used to decide if scaling should be done
             based on the ratio of the scaling factors.  If SCOND < THRESH,
             scaling is done.

             LARGE and SMALL are threshold values used to decide if scaling should
             be done based on the absolute size of the largest matrix element.
             If AMAX > LARGE or AMAX < SMALL, scaling is done.

       Author:
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Date:
           September 2012

       Definition at line 135 of file zlaqsy.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

Version 3.4.2                   Sat Nov 16 2013                    zlaqsy.f(3)