TESTING/LIN/sgtt01.f(3)    Library Functions Manual    TESTING/LIN/sgtt01.f(3)

NAME
       TESTING/LIN/sgtt01.f

SYNOPSIS
   Functions/Subroutines
       subroutine sgtt01 (n, dl, d, du, dlf, df, duf, du2, ipiv, work, ldwork,
           rwork, resid)
           SGTT01

Function/Subroutine Documentation
   subroutine sgtt01 (integer n, real, dimension( * ) dl, real, dimension( * )
       d, real, dimension( * ) du, real, dimension( * ) dlf, real, dimension(
       * ) df, real, dimension( * ) duf, real, dimension( * ) du2, integer,
       dimension( * ) ipiv, real, dimension( ldwork, * ) work, integer ldwork,
       real, dimension( * ) rwork, real resid)
       SGTT01

       Purpose:


           !>
           !> SGTT01 reconstructs a tridiagonal matrix A from its LU factorization
           !> and computes the residual
           !>    norm(L*U - A) / ( norm(A) * EPS ),
           !> where EPS is the machine epsilon.
           !>

       Parameters
           N

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

           DL

           !>          DL is REAL array, dimension (N-1)
           !>          The (n-1) sub-diagonal elements of A.
           !>

           D

           !>          D is REAL array, dimension (N)
           !>          The diagonal elements of A.
           !>

           DU

           !>          DU is REAL array, dimension (N-1)
           !>          The (n-1) super-diagonal elements of A.
           !>

           DLF

           !>          DLF is REAL array, dimension (N-1)
           !>          The (n-1) multipliers that define the matrix L from the
           !>          LU factorization of A.
           !>

           DF

           !>          DF is REAL array, dimension (N)
           !>          The n diagonal elements of the upper triangular matrix U from
           !>          the LU factorization of A.
           !>

           DUF

           !>          DUF is REAL array, dimension (N-1)
           !>          The (n-1) elements of the first super-diagonal of U.
           !>

           DU2

           !>          DU2 is REAL array, dimension (N-2)
           !>          The (n-2) elements of the second super-diagonal of U.
           !>

           IPIV

           !>          IPIV is INTEGER array, dimension (N)
           !>          The pivot indices; for 1 <= i <= n, row i of the matrix was
           !>          interchanged with row IPIV(i).  IPIV(i) will always be either
           !>          i or i+1; IPIV(i) = i indicates a row interchange was not
           !>          required.
           !>

           WORK

           !>          WORK is REAL array, dimension (LDWORK,N)
           !>

           LDWORK

           !>          LDWORK is INTEGER
           !>          The leading dimension of the array WORK.  LDWORK >= max(1,N).
           !>

           RWORK

           !>          RWORK is REAL array, dimension (N)
           !>

           RESID

           !>          RESID is REAL
           !>          The scaled residual:  norm(L*U - A) / (norm(A) * EPS)
           !>

       Author
           Univ. of Tennessee


           Univ. of California Berkeley


           Univ. of Colorado Denver


           NAG Ltd.

       Definition at line 132 of file sgtt01.f.

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

LAPACK                          Version 3.12.0         TESTING/LIN/sgtt01.f(3)