dlarrc.f(3) LAPACK dlarrc.f(3)
**NAME**
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 (characterJOBT, integerN, double precisionVL, double precisionVU, double
precision, dimension( * )D, double precision, dimension( * )E, double precisionPIVMIN,
integerEIGCNT, integerLCNT, integerRCNT, integerINFO)
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
VU
VU is DOUBLE PRECISION
The lower and upper bounds 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.
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 136 of file dlarrc.f.
**Author**
Generated automatically by Doxygen for LAPACK from the source code.
**Version 3.4.2** Tue Sep 25 2012 dlarrc.f(3)