SRC/dlarrc.f(3)            Library Functions Manual            SRC/dlarrc.f(3)

NAME
       SRC/dlarrc.f

SYNOPSIS
   Functions/Subroutines
       subroutine dlarrc (jobt, n, vl, vu, d, e, pivmin, eigcnt, lcnt, rcnt,
           info)
           DLARRC computes the number of eigenvalues of the symmetric
           tridiagonal matrix.

Function/Subroutine Documentation
   subroutine dlarrc (character jobt, integer n, double precision vl, double
       precision vu, double precision, dimension( * ) d, double precision,
       dimension( * ) e, double precision pivmin, integer eigcnt, integer
       lcnt, integer rcnt, integer info)
       DLARRC computes the number of eigenvalues of the symmetric tridiagonal
       matrix.

       Purpose:


           !>
           !> Find the number of eigenvalues of the symmetric tridiagonal matrix T
           !> that are in the interval (VL,VU] if JOBT = 'T', and of L D L^T
           !> if JOBT = 'L'.
           !>

       Parameters
           JOBT

           !>          JOBT is CHARACTER*1
           !>          = 'T':  Compute Sturm count for matrix T.
           !>          = 'L':  Compute Sturm count for matrix L D L^T.
           !>

           N

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

           VL

           !>          VL is DOUBLE PRECISION
           !>          The lower bound for the eigenvalues.
           !>

           VU

           !>          VU is DOUBLE PRECISION
           !>          The upper bound for the eigenvalues.
           !>

           D

           !>          D is DOUBLE PRECISION array, dimension (N)
           !>          JOBT = 'T': The N diagonal elements of the tridiagonal matrix T.
           !>          JOBT = 'L': The N diagonal elements of the diagonal matrix D.
           !>

           E

           !>          E is DOUBLE PRECISION array, dimension (N)
           !>          JOBT = 'T': The N-1 offdiagonal elements of the matrix T.
           !>          JOBT = 'L': The N-1 offdiagonal elements of the matrix L.
           !>

           PIVMIN

           !>          PIVMIN is DOUBLE PRECISION
           !>          The minimum pivot in the Sturm sequence for T.
           !>

           EIGCNT

           !>          EIGCNT is INTEGER
           !>          The number of eigenvalues of the symmetric tridiagonal matrix T
           !>          that are in the interval (VL,VU]
           !>

           LCNT

           !>          LCNT is INTEGER
           !>

           RCNT

           !>          RCNT is INTEGER
           !>          The left and right negcounts of the interval.
           !>

           INFO

           !>          INFO is INTEGER
           !>

       Author
           Univ. of Tennessee


           Univ. of California Berkeley


           Univ. of Colorado Denver


           NAG Ltd.

       Contributors:
           Beresford Parlett, University of California, Berkeley, USA
           Jim Demmel, University of California, Berkeley, USA
           Inderjit Dhillon, University of Texas, Austin, USA
           Osni Marques, LBNL/NERSC, USA
           Christof Voemel, University of California, Berkeley, USA

       Definition at line 135 of file dlarrc.f.

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

LAPACK                          Version 3.12.0                 SRC/dlarrc.f(3)