DLARRR (3) Linux Manual 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
D
The order of the matrix. N > 0.D is DOUBLE PRECISION array, dimension (N)
E
The N diagonal elements of the tridiagonal matrix T.E is DOUBLE PRECISION array, dimension (N)
INFO
On entry, the first (N-1) entries contain the subdiagonal
elements of the tridiagonal matrix T; E(N) is set to ZERO.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.
