dlarrr.f man page

dlarrr.f —

Synopsis

Functions/Subroutines

subroutine dlarrr (N, D, E, INFO)
DLARRR performs tests to decide whether the symmetric tridiagonal matrix T warrants expensive computations which guarantee high relative accuracy in the eigenvalues.

Function/Subroutine Documentation

subroutine dlarrr (integerN, double precision, dimension( * )D, double precision, dimension( * )E, integerINFO)

DLARRR performs tests to decide whether the symmetric tridiagonal matrix T warrants expensive computations which guarantee high relative accuracy in the eigenvalues.

Purpose:

Perform tests to decide whether the symmetric tridiagonal matrix T
warrants expensive computations which guarantee high relative accuracy
in the eigenvalues.

Parameters:

N

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

D

D is DOUBLE PRECISION array, dimension (N)
The N diagonal elements of the tridiagonal matrix T.

E

E is DOUBLE PRECISION array, dimension (N)
On entry, the first (N-1) entries contain the subdiagonal
elements of the tridiagonal matrix T; E(N) is set to ZERO.

INFO

INFO is INTEGER
INFO = 0(default) : the matrix warrants computations preserving
                    relative accuracy.
INFO = 1          : the matrix warrants computations guaranteeing
                    only absolute accuracy.

Author:

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Date:

September 2012

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 95 of file dlarrr.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

dlarrr(3) is an alias of dlarrr.f(3).

Sat Nov 16 2013 Version 3.4.2 LAPACK