larrc - larrc: step in stemr

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subroutinedlarrc(characterjobt,integern,doubleprecisionvl,doubleprecisionvu,doubleprecision,dimension(*)d,doubleprecision,dimension(*)e,doubleprecisionpivmin,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'. ParametersJOBT 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 The lower bound for the eigenvalues. VU VU is DOUBLE PRECISION The upper bound 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. 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 subroutineslarrc(characterjobt,integern,realvl,realvu,real,dimension(*)d,real,dimension(*)e,realpivmin,integereigcnt,integerlcnt,integerrcnt,integerinfo)SLARRC 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'. ParametersJOBT 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 REAL The lower bound for the eigenvalues. VU VU is REAL The upper bound for the eigenvalues. D D is REAL 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 REAL 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 REAL 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. 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

larrc - larrc: step in stemr

Functions subroutine dlarrc (jobt, n, vl, vu, d, e, pivmin, eigcnt, lcnt, rcnt, info) DLARRC computes the number of eigenvalues of the symmetric tridiagonal matrix. subroutine slarrc (jobt, n, vl, vu, d, e, pivmin, eigcnt, lcnt, rcnt, info) SLARRC computes the number of eigenvalues of the symmetric tridiagonal matrix.