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# zlansy

```
NAME
ZLANSY - return the value of the one norm, or the Frobenius
norm, or the infinity norm, or the element of largest abso-
lute value of a complex symmetric matrix A

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

CHARACTER    NORM, UPLO

INTEGER      LDA, N

DOUBLE       PRECISION WORK( * )

COMPLEX*16   A( LDA, * )

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

DESCRIPTION
ZLANSY returns the value

ZLANSY = ( 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 ZLANSY 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,
ZLANSY is set to zero.

A       (input) COMPLEX*16 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'; oth-
erwise, WORK is not referenced.
```