dlanhs.f(3) LAPACK dlanhs.f(3)NAMEdlanhs.f-
SYNOPSIS
Functions/Subroutines
DOUBLE PRECISION function dlanhs (NORM, N, A, LDA, WORK)
DLANHS returns the value of the 1-norm, Frobenius norm, infinity-
norm, 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 1-norm, Frobenius norm, infinity-norm,
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 sub-diagonal 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)
