TESTING/LIN/ssyt01_3.f(3)  Library Functions Manual  TESTING/LIN/ssyt01_3.f(3)

NAME
       TESTING/LIN/ssyt01_3.f

SYNOPSIS
   Functions/Subroutines
       subroutine ssyt01_3 (uplo, n, a, lda, afac, ldafac, e, ipiv, c, ldc,
           rwork, resid)
           SSYT01_3

Function/Subroutine Documentation
   subroutine ssyt01_3 (character uplo, integer n, real, dimension( lda, * )
       a, integer lda, real, dimension( ldafac, * ) afac, integer ldafac,
       real, dimension( * ) e, integer, dimension( * ) ipiv, real, dimension(
       ldc, * ) c, integer ldc, real, dimension( * ) rwork, real resid)
       SSYT01_3

       Purpose:


            SSYT01_3 reconstructs a symmetric indefinite matrix A from its
            block L*D*L' or U*D*U' factorization computed by SSYTRF_RK
            (or SSYTRF_BK) and computes the residual
               norm( C - A ) / ( N * norm(A) * EPS ),
            where C is the reconstructed matrix and EPS is the machine epsilon.

       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 number of rows and columns of the matrix A.  N >= 0.

           A

                     A is DOUBLE PRECISION array, dimension (LDA,N)
                     The original symmetric matrix A.

           LDA

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

           AFAC

                     AFAC is DOUBLE PRECISION array, dimension (LDAFAC,N)
                     Diagonal of the block diagonal matrix D and factors U or L
                     as computed by SSYTRF_RK and SSYTRF_BK:
                       a) ONLY diagonal elements of the symmetric block diagonal
                          matrix D on the diagonal of A, i.e. D(k,k) = A(k,k);
                          (superdiagonal (or subdiagonal) elements of D
                           should be provided on entry in array E), and
                       b) If UPLO = 'U': factor U in the superdiagonal part of A.
                          If UPLO = 'L': factor L in the subdiagonal part of A.

           LDAFAC

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

           E

                     E is DOUBLE PRECISION array, dimension (N)
                     On entry, contains the superdiagonal (or subdiagonal)
                     elements of the symmetric block diagonal matrix D
                     with 1-by-1 or 2-by-2 diagonal blocks, where
                     If UPLO = 'U': E(i) = D(i-1,i),i=2:N, E(1) not referenced;
                     If UPLO = 'L': E(i) = D(i+1,i),i=1:N-1, E(N) not referenced.

           IPIV

                     IPIV is INTEGER array, dimension (N)
                     The pivot indices from SSYTRF_RK (or SSYTRF_BK).

           C

                     C is DOUBLE PRECISION array, dimension (LDC,N)

           LDC

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

           RWORK

                     RWORK is DOUBLE PRECISION array, dimension (N)

           RESID

                     RESID is DOUBLE PRECISION
                     If UPLO = 'L', norm(L*D*L' - A) / ( N * norm(A) * EPS )
                     If UPLO = 'U', norm(U*D*U' - A) / ( N * norm(A) * EPS )

       Author
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Definition at line 138 of file ssyt01_3.f.

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

LAPACK                          Version 3.12.0       TESTING/LIN/ssyt01_3.f(3)