ZLANHT(3f)          LAPACK auxiliary routine (version 3.1)          ZLANHT(3f)



NAME
       ZLANHT - 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 tridiagonal matrix A

SYNOPSIS
       DOUBLE PRECISION FUNCTION ZLANHT( NORM, N, D, E )

           CHARACTER    NORM

           INTEGER      N

           DOUBLE       PRECISION D( * )

           COMPLEX*16   E( * )

PURPOSE
       ZLANHT  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 tridiagonal matrix A.


DESCRIPTION
       ZLANHT returns the value

          ZLANHT = ( 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 ZLANHT as described
               above.

       N       (input) INTEGER
               The order of the matrix A.  N >= 0.  When N = 0, ZLANHT is set
               to zero.

       D       (input) DOUBLE PRECISION array, dimension (N)
               The diagonal elements of A.

       E       (input) COMPLEX*16 array, dimension (N-1)
               The (n-1) sub-diagonal or super-diagonal elements of A.



 LAPACK auxiliary routine (versioNovember 2006                      ZLANHT(3f)
