1CLANHB(1)           LAPACK auxiliary routine (version 3.2)           CLANHB(1)
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NAME

6       CLANHB  -  returns the value of the one norm, or the Frobenius norm, or
7       the infinity norm, or the element of largest absolute value of an n  by
8       n hermitian band matrix A, with k super-diagonals
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SYNOPSIS

11       REAL FUNCTION CLANHB( NORM, UPLO, N, K, AB, LDAB, WORK )
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13           CHARACTER NORM, UPLO
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15           INTEGER   K, LDAB, N
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17           REAL      WORK( * )
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19           COMPLEX   AB( LDAB, * )
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PURPOSE

22       CLANHB   returns  the value of the one norm,  or the Frobenius norm, or
23       the  infinity norm,  or the element of  largest absolute value  of an n
24       by n hermitian band matrix A,  with k super-diagonals.
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DESCRIPTION

27       CLANHB returns the value
28          CLANHB = ( max(abs(A(i,j))), NORM = 'M' or 'm'
29                   (
30                   ( norm1(A),         NORM = '1', 'O' or 'o'
31                   (
32                   ( normI(A),         NORM = 'I' or 'i'
33                   (
34                   (  normF(A),          NORM  =  'F',  'f',  'E' or 'e' where
35       norm1  denotes the  one norm of a matrix (maximum  column  sum),  normI
36       denotes  the   infinity  norm  of a matrix  (maximum row sum) and normF
37       denotes the  Frobenius  norm  of  a  matrix  (square  root  of  sum  of
38       squares).   Note  that   max(abs(A(i,j)))   is  not a consistent matrix
39       norm.
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ARGUMENTS

42       NORM    (input) CHARACTER*1
43               Specifies the value to  be  returned  in  CLANHB  as  described
44               above.
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46       UPLO    (input) CHARACTER*1
47               Specifies  whether  the  upper  or lower triangular part of the
48               band matrix A is supplied.  = 'U':  Upper triangular
49               = 'L':  Lower triangular
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51       N       (input) INTEGER
52               The order of the matrix A.  N >= 0.  When N = 0, CLANHB is  set
53               to zero.
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55       K       (input) INTEGER
56               The  number  of  super-diagonals  or  sub-diagonals of the band
57               matrix A.  K >= 0.
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59       AB      (input) COMPLEX array, dimension (LDAB,N)
60               The upper or lower triangle of the  hermitian  band  matrix  A,
61               stored  in  the  first K+1 rows of AB.  The j-th column of A is
62               stored in the j-th column of the array AB as follows: if UPLO =
63               'U',  AB(k+1+i-j,j)  =  A(i,j)  for max(1,j-k)<=i<=j; if UPLO =
64               'L', AB(1+i-j,j)   = A(i,j) for  j<=i<=min(n,j+k).   Note  that
65               the  imaginary  parts  of the diagonal elements need not be set
66               and are assumed to be zero.
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68       LDAB    (input) INTEGER
69               The leading dimension of the array AB.  LDAB >= K+1.
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71       WORK    (workspace) REAL array, dimension (MAX(1,LWORK)),
72               where LWORK >= N when NORM = 'I' or '1' or 'O'; otherwise, WORK
73               is not referenced.
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77 LAPACK auxiliary routine (versionNo3v.e2m)ber 2008                       CLANHB(1)
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