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RedHat 9 (Linux i386) - man page for dlansy (redhat section l)

DLANSY(l)					)					DLANSY(l)

NAME
       DLANSY - return the value of the one norm, or the Frobenius norm, or the infinity norm, or
       the element of largest absolute value of a real symmetric matrix A

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

	   CHARACTER	NORM, UPLO

	   INTEGER	LDA, N

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

PURPOSE
       DLANSY returns the value of the one norm, or the Frobenius norm, or the infinity norm,  or
       the element of largest absolute value of a real symmetric matrix A.

DESCRIPTION
       DLANSY returns the value

	  DLANSY = ( 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 DLANSY as described above.

       UPLO    (input) CHARACTER*1
	       Specifies whether the upper or lower triangular part of the symmetric matrix A  is
	       to be referenced.  = 'U':  Upper triangular part of A is referenced
	       = 'L':  Lower triangular part of A is referenced

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

       A       (input) DOUBLE PRECISION array, dimension (LDA,N)
	       The  symmetric  matrix A.  If UPLO = 'U', the leading n by n upper triangular part
	       of A contains the upper triangular part of the matrix A, and  the  strictly  lower
	       triangular  part  of A is not referenced.  If UPLO = 'L', the leading n by n lower
	       triangular part of A contains the lower triangular part of the matrix A,  and  the
	       strictly upper triangular part of A 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' or '1' or 'O'; otherwise, WORK is not referenced.

LAPACK version 3.0			   15 June 2000 				DLANSY(l)


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