2. EL 8
  3. lapack
  4. slarrr.f(3)

Scroll to navigation

slarrr.f(3) LAPACK slarrr.f(3)

NAME

slarrr.f

SYNOPSIS

Functions/Subroutines


subroutine slarrr (N, D, E, INFO)
SLARRR 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 slarrr (integer N, real, dimension( * ) D, real, dimension( * ) E, integer INFO)

SLARRR 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 REAL array, dimension (N)


          The N diagonal elements of the tridiagonal matrix T.

E



          E is REAL 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:

June 2017

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 96 of file slarrr.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Tue Nov 14 2017 Version 3.8.0