GNU/Linux |
CentOS 4.8 |
i386 |
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clansy(l) |
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CLANSY - return the value of the one norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a complex symmetric matrix A
REAL FUNCTION |
CLANSY( NORM, UPLO, N, A, LDA, WORK ) |
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CHARACTER |
NORM, UPLO |
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INTEGER |
LDA, N |
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REAL |
WORK( * ) |
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COMPLEX |
A( LDA, * ) |
CLANSY 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 symmetric matrix A.
CLANSY returns the value
CLANSY = (
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 matrix norm.
NORM (input) CHARACTER*1
Specifies the value to be returned in CLANSY as described above.
UPLO (input) CHARACTER*1
Specifies whether the upper or
lower triangular part of the symmetric matrix A is to be
referenced. = ’U’: Upper triangular 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, CLANSY is set to zero.
A (input) COMPLEX array, dimension (LDA,N)
The symmetric 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 triangular part of A contains the lower triangular part of the matrix A, and the strictly upper triangular part of A is not referenced.
LDA (input) INTEGER
The leading dimension of the array A. LDA >= max(N,1).
WORK (workspace) REAL array, dimension (LWORK),
where LWORK >= N when NORM = ’I’ or ’1’ or ’O’; otherwise, WORK is not referenced.
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clansy(l) | ![]() |