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# zlanhe

```
NAME
ZLANHE - 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 hermitian matrix A

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

CHARACTER    NORM, UPLO

INTEGER      LDA, N

DOUBLE       PRECISION WORK( * )

COMPLEX*16   A( LDA, * )

PURPOSE
ZLANHE  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 hermitian matrix A.

DESCRIPTION
ZLANHE returns the value

ZLANHE = ( 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 ZLANHE as
described above.

UPLO    (input) CHARACTER*1
Specifies whether the upper or lower triangular part
of the hermitian 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,
ZLANHE is set to zero.

A       (input) COMPLEX*16 array, dimension (LDA,N)
The hermitian 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. Note that the imaginary parts
of the diagonal elements need not be set and are
assumed to be zero.

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.
```