redhat man page for dlanhs

DLANHS(l)								 )								 DLANHS(l)

NAME
       DLANHS  - return the value of the one norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a Hes-
       senberg matrix A

SYNOPSIS
       DOUBLE PRECISION FUNCTION DLANHS( NORM, N, A, LDA, WORK )

	   CHARACTER	NORM

	   INTEGER	LDA, N

	   DOUBLE	PRECISION A( LDA, * ), WORK( * )

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  Hes-
       senberg matrix A.

DESCRIPTION
       DLANHS returns the value

	  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  matrix norm.

ARGUMENTS
       NORM    (input) CHARACTER*1
	       Specifies the value to be returned in DLANHS as described above.

       N       (input) INTEGER
	       The order of the matrix A.  N >= 0.  When N = 0, DLANHS is set to zero.

       A       (input) 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     (input) INTEGER
	       The leading dimension of the array A.  LDA >= max(N,1).

       WORK    (workspace) DOUBLE PRECISION array, dimension (LWORK),
	       where LWORK >= N when NORM = 'I'; otherwise, WORK is not referenced.

LAPACK version 3.0						   15 June 2000 							 DLANHS(l)