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# clanhe

```
NAME
CLANHE - 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
REAL FUNCTION CLANHE( NORM, UPLO, N, A, LDA, WORK )

CHARACTER NORM, UPLO

INTEGER   LDA, N

REAL      WORK( * )

COMPLEX   A( LDA, * )

PURPOSE
CLANHE  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
CLANHE returns the value

CLANHE = ( 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 CLANHE 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,
CLANHE is set to zero.

A       (input) COMPLEX 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) REAL array, dimension (LWORK),
where LWORK >= N when NORM = 'I' or '1' or 'O'; oth-
erwise, WORK is not referenced.
```