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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.