chpcon.f man page
subroutine chpcon (UPLO, N, AP, IPIV, ANORM, RCOND, WORK, INFO)
subroutine chpcon (character UPLO, integer N, complex, dimension( * ) AP, integer, dimension( * ) IPIV, real ANORM, real RCOND, complex, dimension( * ) WORK, integer INFO)
CHPCON estimates the reciprocal of the condition number of a complex Hermitian packed matrix A using the factorization A = U*D*U**H or A = L*D*L**H computed by CHPTRF. An estimate is obtained for norm(inv(A)), and the reciprocal of the condition number is computed as RCOND = 1 / (ANORM * norm(inv(A))).
UPLO is CHARACTER*1 Specifies whether the details of the factorization are stored as an upper or lower triangular matrix. = 'U': Upper triangular, form is A = U*D*U**H; = 'L': Lower triangular, form is A = L*D*L**H.
N is INTEGER The order of the matrix A. N >= 0.
AP is COMPLEX array, dimension (N*(N+1)/2) The block diagonal matrix D and the multipliers used to obtain the factor U or L as computed by CHPTRF, stored as a packed triangular matrix.
IPIV is INTEGER array, dimension (N) Details of the interchanges and the block structure of D as determined by CHPTRF.
ANORM is REAL The 1-norm of the original matrix A.
RCOND is REAL The reciprocal of the condition number of the matrix A, computed as RCOND = 1/(ANORM * AINVNM), where AINVNM is an estimate of the 1-norm of inv(A) computed in this routine.
WORK is COMPLEX array, dimension (2*N)
INFO is INTEGER = 0: successful exit < 0: if INFO = -i, the i-th argument had an illegal value
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
Definition at line 120 of file chpcon.f.
Generated automatically by Doxygen for LAPACK from the source code.
The man page chpcon(3) is an alias of chpcon.f(3).