1CLANHT(1)           LAPACK auxiliary routine (version 3.1)           CLANHT(1)
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NAME

6       CLANHT  -  the  value  of  the  one norm, or the Frobenius norm, or the
7       infinity norm, or the element of largest absolute value  of  a  complex
8       Hermitian tridiagonal matrix A
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SYNOPSIS

11       REAL FUNCTION CLANHT( NORM, N, D, E )
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13           CHARACTER NORM
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15           INTEGER   N
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17           REAL      D( * )
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19           COMPLEX   E( * )
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PURPOSE

22       CLANHT   returns  the value of the one norm,  or the Frobenius norm, or
23       the  infinity norm,  or the  element of  largest absolute value   of  a
24       complex Hermitian tridiagonal matrix A.
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DESCRIPTION

28       CLANHT returns the value
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30          CLANHT = ( max(abs(A(i,j))), NORM = 'M' or 'm'
31                   (
32                   ( norm1(A),         NORM = '1', 'O' or 'o'
33                   (
34                   ( normI(A),         NORM = 'I' or 'i'
35                   (
36                   ( normF(A),         NORM = 'F', 'f', 'E' or 'e'
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38       where   norm1   denotes the  one norm of a matrix (maximum column sum),
39       normI  denotes the  infinity norm  of a matrix  (maximum row  sum)  and
40       normF   denotes  the  Frobenius norm of a matrix (square root of sum of
41       squares).  Note that  max(abs(A(i,j)))   is  not  a  consistent  matrix
42       norm.
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ARGUMENTS

46       NORM    (input) CHARACTER*1
47               Specifies  the  value  to  be  returned  in CLANHT as described
48               above.
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50       N       (input) INTEGER
51               The order of the matrix A.  N >= 0.  When N = 0, CLANHT is  set
52               to zero.
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54       D       (input) REAL array, dimension (N)
55               The diagonal elements of A.
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57       E       (input) COMPLEX array, dimension (N-1)
58               The (n-1) sub-diagonal or super-diagonal elements of A.
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62 LAPACK auxiliary routine (versionNo3v.e1m)ber 2006                       CLANHT(1)