TESTING/LIN/dpbt01.f(3)    Library Functions Manual    TESTING/LIN/dpbt01.f(3)

NAME
       TESTING/LIN/dpbt01.f

SYNOPSIS
   Functions/Subroutines
       subroutine dpbt01 (uplo, n, kd, a, lda, afac, ldafac, rwork, resid)
           DPBT01

Function/Subroutine Documentation
   subroutine dpbt01 (character uplo, integer n, integer kd, double precision,
       dimension( lda, * ) a, integer lda, double precision, dimension(
       ldafac, * ) afac, integer ldafac, double precision, dimension( * )
       rwork, double precision resid)
       DPBT01

       Purpose:


            DPBT01 reconstructs a symmetric positive definite band matrix A from
            its L*L' or U'*U factorization and computes the residual
               norm( L*L' - A ) / ( N * norm(A) * EPS ) or
               norm( U'*U - A ) / ( N * norm(A) * EPS ),
            where EPS is the machine epsilon, L' is the conjugate transpose of
            L, and U' is the conjugate transpose of U.

       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.

           KD

                     KD is INTEGER
                     The number of super-diagonals of the matrix A if UPLO = 'U',
                     or the number of sub-diagonals if UPLO = 'L'.  KD >= 0.

           A

                     A is DOUBLE PRECISION array, dimension (LDA,N)
                     The original symmetric band matrix A.  If UPLO = 'U', the
                     upper triangular part of A is stored as a band matrix; if
                     UPLO = 'L', the lower triangular part of A is stored.  The
                     columns of the appropriate triangle are stored in the columns
                     of A and the diagonals of the triangle are stored in the rows
                     of A.  See DPBTRF for further details.

           LDA

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

           AFAC

                     AFAC is DOUBLE PRECISION array, dimension (LDAFAC,N)
                     The factored form of the matrix A.  AFAC contains the factor
                     L or U from the L*L' or U'*U factorization in band storage
                     format, as computed by DPBTRF.

           LDAFAC

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

           RWORK

                     RWORK is DOUBLE PRECISION array, dimension (N)

           RESID

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

       Author
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Definition at line 117 of file dpbt01.f.

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

LAPACK                          Version 3.12.0         TESTING/LIN/dpbt01.f(3)