Provided by: liblapack-doc_3.3.1-1_all

NAME

```       LAPACK-3 - 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

```

SYNOPSIS

```       REAL FUNCTION SLANSY( NORM, UPLO, N, A, LDA, WORK )

CHARACTER NORM, UPLO

INTEGER   LDA, N

REAL      A( LDA, * ), WORK( * )

```

PURPOSE

```       SLANSY  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

```        SLANSY returns the value
SLANSY = ( 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.

```

ARGUMENTS

```        NORM    (input) CHARACTER*1
Specifies the value to be returned in SLANSY 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, SLANSY is
set to zero.

A       (input) REAL 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) REAL array, dimension (MAX(1,LWORK)),
where LWORK >= N when NORM = 'I' or '1' or 'O'; otherwise,
WORK is not referenced.

LAPACK auxiliary routine (version 3.2)     April 2011                            SLANSY(3lapack)
```