CLANHE(1) LAPACK auxiliary routine (version 3.2) CLANHE(1)NAME
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 com‐
plex 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 consistent 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 triangu‐
lar 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 trian‐
gular 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 ele‐
ments 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 (MAX(1,LWORK)),
where LWORK >= N when NORM = 'I' or '1' or 'O'; otherwise, WORK
is not referenced.
LAPACK auxiliary routine (versioNovember 2008 CLANHE(1)