dlarrc.f (3) - Linux Manuals
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.
NN is INTEGER The order of the matrix. N > 0.
VLVL is DOUBLE PRECISION
VUVU is DOUBLE PRECISION The lower and upper bounds for the eigenvalues.
DD 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.
EE 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.
PIVMINPIVMIN is DOUBLE PRECISION The minimum pivot in the Sturm sequence for T.
EIGCNTEIGCNT is INTEGER The number of eigenvalues of the symmetric tridiagonal matrix T that are in the interval (VL,VU]
LCNTLCNT is INTEGER
RCNTRCNT is INTEGER The left and right negcounts of the interval.
INFOINFO 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.