SRC/zptcon.f(3) Library Functions Manual SRC/zptcon.f(3) NAME SRC/zptcon.f SYNOPSIS Functions/Subroutines subroutine zptcon (n, d, e, anorm, rcond, rwork, info) ZPTCON Function/Subroutine Documentation subroutine zptcon (integer n, double precision, dimension( * ) d, complex*16, dimension( * ) e, double precision anorm, double precision rcond, double precision, dimension( * ) rwork, integer info) ZPTCON Purpose: !> !> ZPTCON computes the reciprocal of the condition number (in the !> 1-norm) of a complex Hermitian positive definite tridiagonal matrix !> using the factorization A = L*D*L**H or A = U**H*D*U computed by !> ZPTTRF. !> !> Norm(inv(A)) is computed by a direct method, and the reciprocal of !> the condition number is computed as !> RCOND = 1 / (ANORM * norm(inv(A))). !> Parameters N !> N is INTEGER !> The order of the matrix A. N >= 0. !> D !> D is DOUBLE PRECISION array, dimension (N) !> The n diagonal elements of the diagonal matrix D from the !> factorization of A, as computed by ZPTTRF. !> E !> E is COMPLEX*16 array, dimension (N-1) !> The (n-1) off-diagonal elements of the unit bidiagonal factor !> U or L from the factorization of A, as computed by ZPTTRF. !> ANORM !> ANORM is DOUBLE PRECISION !> The 1-norm of the original matrix A. !> RCOND !> RCOND is DOUBLE PRECISION !> The reciprocal of the condition number of the matrix A, !> computed as RCOND = 1/(ANORM * AINVNM), where AINVNM is the !> 1-norm of inv(A) computed in this routine. !> RWORK !> RWORK is DOUBLE PRECISION array, dimension (N) !> INFO !> INFO is INTEGER !> = 0: successful exit !> < 0: if INFO = -i, the i-th argument had an illegal value !> Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. Further Details: !> !> The method used is described in Nicholas J. Higham, , SIAM J. Sci. Stat. Comput., Vol. 7, No. 1, January 1986. !> Definition at line 118 of file zptcon.f. Author Generated automatically by Doxygen for LAPACK from the source code. LAPACK Version 3.12.0 SRC/zptcon.f(3)