table of contents
/home/abuild/rpmbuild/BUILD/lapack-3.12.0/SRC/ztbcon.f(3) | Library Functions Manual | /home/abuild/rpmbuild/BUILD/lapack-3.12.0/SRC/ztbcon.f(3) |
NAME¶
/home/abuild/rpmbuild/BUILD/lapack-3.12.0/SRC/ztbcon.f
SYNOPSIS¶
Functions/Subroutines¶
subroutine ZTBCON (norm, uplo, diag, n, kd, ab, ldab,
rcond, work, rwork, info)
ZTBCON
Function/Subroutine Documentation¶
subroutine ZTBCON (character norm, character uplo, character diag, integer n, integer kd, complex*16, dimension( ldab, * ) ab, integer ldab, double precision rcond, complex*16, dimension( * ) work, double precision, dimension( * ) rwork, integer info)¶
ZTBCON
Purpose:
!> !> ZTBCON estimates the reciprocal of the condition number of a !> triangular band matrix A, in either the 1-norm or the infinity-norm. !> !> The norm of A is computed and an estimate is obtained for !> norm(inv(A)), then the reciprocal of the condition number is !> computed as !> RCOND = 1 / ( norm(A) * norm(inv(A)) ). !>
Parameters
NORM
!> NORM is CHARACTER*1 !> Specifies whether the 1-norm condition number or the !> infinity-norm condition number is required: !> = '1' or 'O': 1-norm; !> = 'I': Infinity-norm. !>
UPLO
!> UPLO is CHARACTER*1 !> = 'U': A is upper triangular; !> = 'L': A is lower triangular. !>
DIAG
!> DIAG is CHARACTER*1 !> = 'N': A is non-unit triangular; !> = 'U': A is unit triangular. !>
N
!> N is INTEGER !> The order of the matrix A. N >= 0. !>
KD
!> KD is INTEGER !> The number of superdiagonals or subdiagonals of the !> triangular band matrix A. KD >= 0. !>
AB
!> AB is COMPLEX*16 array, dimension (LDAB,N) !> The upper or lower triangular band matrix A, stored in the !> first kd+1 rows of the array. The j-th column of A is stored !> in the j-th column of the array AB as follows: !> if UPLO = 'U', AB(kd+1+i-j,j) = A(i,j) for max(1,j-kd)<=i<=j; !> if UPLO = 'L', AB(1+i-j,j) = A(i,j) for j<=i<=min(n,j+kd). !> If DIAG = 'U', the diagonal elements of A are not referenced !> and are assumed to be 1. !>
LDAB
!> LDAB is INTEGER !> The leading dimension of the array AB. LDAB >= KD+1. !>
RCOND
!> RCOND is DOUBLE PRECISION !> The reciprocal of the condition number of the matrix A, !> computed as RCOND = 1/(norm(A) * norm(inv(A))). !>
WORK
!> WORK is COMPLEX*16 array, dimension (2*N) !>
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.
Definition at line 141 of file ztbcon.f.
Author¶
Generated automatically by Doxygen for LAPACK from the source code.
Version 3.12.0 | LAPACK |