
dlanhs.f(3) LAPACK dlanhs.f(3)
NAME
dlanhs.f 
SYNOPSIS
Functions/Subroutines
DOUBLE PRECISION function dlanhs (NORM, N, A, LDA, WORK)
DLANHS returns the value of the 1norm, Frobenius norm, infinitynorm, or the largest
absolute value of any element of an upper Hessenberg matrix.
Function/Subroutine Documentation
DOUBLE PRECISION function dlanhs (characterNORM, integerN, double precision, dimension( lda, *
)A, integerLDA, double precision, dimension( * )WORK)
DLANHS returns the value of the 1norm, Frobenius norm, infinitynorm, or the largest
absolute value of any element of an upper Hessenberg matrix.
Purpose:
DLANHS returns the value of the one norm, or the Frobenius norm, or
the infinity norm, or the element of largest absolute value of a
Hessenberg matrix A.
Returns:
DLANHS
DLANHS = ( max(abs(A(i,j))), NORM = 'M' or 'm'
(
( norm1(A), NORM = '1', 'O' or 'o'
(
( normI(A), NORM = 'I' or 'i'
(
( normF(A), NORM = 'F', 'f', 'E' or 'e'
where norm1 denotes the one norm of a matrix (maximum column sum),
normI denotes the infinity norm of a matrix (maximum row sum) and
normF denotes the Frobenius norm of a matrix (square root of sum of
squares). Note that max(abs(A(i,j))) is not a consistent matrix norm.
Parameters:
NORM
NORM is CHARACTER*1
Specifies the value to be returned in DLANHS as described
above.
N
N is INTEGER
The order of the matrix A. N >= 0. When N = 0, DLANHS is
set to zero.
A
A is DOUBLE PRECISION array, dimension (LDA,N)
The n by n upper Hessenberg matrix A; the part of A below the
first subdiagonal is not referenced.
LDA
LDA is INTEGER
The leading dimension of the array A. LDA >= max(N,1).
WORK
WORK is DOUBLE PRECISION array, dimension (MAX(1,LWORK)),
where LWORK >= N when NORM = 'I'; otherwise, WORK is not
referenced.
Author:
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Date:
September 2012
Definition at line 109 of file dlanhs.f.
Author
Generated automatically by Doxygen for LAPACK from the source code.
Version 3.4.2 Tue Sep 25 2012 dlanhs.f(3) 
