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zla_syrpvgrw.f(3)                   LAPACK                   zla_syrpvgrw.f(3)


NAME

       zla_syrpvgrw.f -


SYNOPSIS

   Functions/Subroutines
       DOUBLE PRECISION function zla_syrpvgrw (UPLO, N, INFO, A, LDA, AF,
           LDAF, IPIV, WORK)
           ZLA_SYRPVGRW computes the reciprocal pivot growth factor
           norm(A)/norm(U) for a symmetric indefinite matrix.

Function/Subroutine Documentation
   DOUBLE PRECISION function zla_syrpvgrw (character*1UPLO, integerN,
       integerINFO, complex*16, dimension( lda, * )A, integerLDA, complex*16,
       dimension( ldaf, * )AF, integerLDAF, integer, dimension( * )IPIV,
       double precision, dimension( * )WORK)
       ZLA_SYRPVGRW computes the reciprocal pivot growth factor
       norm(A)/norm(U) for a symmetric indefinite matrix.

       Purpose:

            ZLA_SYRPVGRW computes the reciprocal pivot growth factor
            norm(A)/norm(U). The "max absolute element" norm is used. If this is
            much less than 1, the stability of the LU factorization of the
            (equilibrated) matrix A could be poor. This also means that the
            solution X, estimated condition numbers, and error bounds could be
            unreliable.

       Parameters:
           UPLO

                     UPLO is CHARACTER*1
                  = 'U':  Upper triangle of A is stored;
                  = 'L':  Lower triangle of A is stored.

           N

                     N is INTEGER
                The number of linear equations, i.e., the order of the
                matrix A.  N >= 0.

           INFO

                     INFO is INTEGER
                The value of INFO returned from ZSYTRF, .i.e., the pivot in
                column INFO is exactly 0.

           A

                     A is COMPLEX*16 array, dimension (LDA,N)
                On entry, the N-by-N matrix A.

           LDA

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

           AF

                     AF is COMPLEX*16 array, dimension (LDAF,N)
                The block diagonal matrix D and the multipliers used to
                obtain the factor U or L as computed by ZSYTRF.

           LDAF

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

           IPIV

                     IPIV is INTEGER array, dimension (N)
                Details of the interchanges and the block structure of D
                as determined by ZSYTRF.

           WORK

                     WORK is COMPLEX*16 array, dimension (2*N)

       Author:
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Date:
           September 2012

       Definition at line 123 of file zla_syrpvgrw.f.

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

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

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