SRC/dsterf.f(3)

NAME
SRC/dsterf.f

SYNOPSIS

  Functions/Subroutines
subroutine dsterf (n, d, e, info)
DSTERF

Function/Subroutine Documentation

  subroutine dsterf (integer n, double precision, dimension( * ) d, double precision, dimension( * ) e, integer info)

DSTERF

Purpose:

    !>
    !> DSTERF computes all eigenvalues of a symmetric tridiagonal matrix
    !> using the Pal-Walker-Kahan variant of the QL or QR algorithm.
    !>

Parameters
    N

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

    D

    !>          D is DOUBLE PRECISION array, dimension (N)
    !>          On entry, the n diagonal elements of the tridiagonal matrix.
    !>          On exit, if INFO = 0, the eigenvalues in ascending order.
    !>

    E

    !>          E is DOUBLE PRECISION array, dimension (N-1)
    !>          On entry, the (n-1) subdiagonal elements of the tridiagonal
    !>          matrix.
    !>          On exit, E has been destroyed.
    !>

    INFO

    !>          INFO is INTEGER
    !>          = 0:  successful exit
    !>          < 0:  if INFO = -i, the i-th argument had an illegal value
    !>          > 0:  the algorithm failed to find all of the eigenvalues in
    !>                a total of 30*N iterations; if INFO = i, then i
    !>                elements of E have not converged to zero.
    !>

Author
    Univ. of Tennessee

    Univ. of California Berkeley

    Univ. of Colorado Denver

    NAG Ltd.

Definition at line 85 of file dsterf.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.