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template<typename T>
void larrc(char *jobt, integer *n, T *vl, T *vu, T *d, T *e, T *pivmin, integer *eigcnt, integer *lcnt, integer *rcnt, integer *info)# LARRC 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 – [in]
JOBT is CHARACTER*1
= ‘T’: Compute Sturm count for matrix T.
= ‘L’: Compute Sturm count for matrix L D L^T.N – [in]
N is INTEGER
The order of the matrix. N > 0.
VL – [in]
VL is REAL
The lower bound for the eigenvalues.
VU – [in]
VU is REAL
The upper bound for the eigenvalues.
D – [in]
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 – [in]
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 – [in]
PIVMIN is REAL
The minimum pivot in the Sturm sequence for T.
EIGCNT – [out]
EIGCNT is INTEGER
The number of eigenvalues of the symmetric tridiagonal matrix T that are in the interval (VL,VU]
LCNT – [out] LCNT is INTEGER
RCNT – [out]
RCNT is INTEGER
The left and right negcounts of the interval.
INFO – [out] INFO is INTEGER