LAPACK  3.4.2 LAPACK: Linear Algebra PACKage
clanht.f File Reference

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## Functions/Subroutines

REAL function clanht (NORM, N, D, E)
CLANHT returns the value of the 1-norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a complex Hermitian tridiagonal matrix.

## Function/Subroutine Documentation

 REAL function clanht ( character NORM, integer N, real, dimension( * ) D, complex, dimension( * ) E )

CLANHT returns the value of the 1-norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a complex Hermitian tridiagonal matrix.

Purpose:
``` CLANHT  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.```
Returns:
CLANHT
```    CLANHT = ( 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.```
Parameters:
 [in] NORM ``` NORM is CHARACTER*1 Specifies the value to be returned in CLANHT as described above.``` [in] N ``` N is INTEGER The order of the matrix A. N >= 0. When N = 0, CLANHT is set to zero.``` [in] D ``` D is REAL array, dimension (N) The diagonal elements of A.``` [in] E ``` E is COMPLEX array, dimension (N-1) The (n-1) sub-diagonal or super-diagonal elements of A.```
Date:
September 2012

Definition at line 102 of file clanht.f.

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