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ZLANSY(1) LAPACK auxiliary routine (version 3.2) ZLANSY(1)

NAME

ZLANSY - 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

SYNOPSIS

FUNCTION ZLANSY( NORM, UPLO, N, A, LDA, WORK )

CHARACTER NORM, UPLO INTEGER LDA, N DOUBLE PRECISION WORK( * ) COMPLEX*16 A( LDA, * )

PURPOSE

ZLANSY 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.

DESCRIPTION

ZLANSY returns the value
ZLANSY = ( 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

Specifies the value to be returned in ZLANSY as described above.
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
The order of the matrix A. N >= 0. When N = 0, ZLANSY is set to zero.
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.
The leading dimension of the array A. LDA >= max(N,1).
where LWORK >= N when NORM = 'I' or '1' or 'O'; otherwise, WORK is not referenced.
November 2008 LAPACK auxiliary routine (version 3.2)