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DLANSYRun Method

Purpose ======= DLANSY returns the value of the one norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a real symmetric matrix A. Description =========== DLANSY returns the value DLANSY = ( 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.

Namespace: DotNumerics.LinearAlgebra.CSLapack
Assembly: DWSIM.MathOps.DotNumerics (in DWSIM.MathOps.DotNumerics.dll) Version: 1.0.0.0 (1.0.0.0)
Syntax
Copy
public double Run(
	string NORM,
	string UPLO,
	int N,
	double[] A,
	int offset_a,
	int LDA,
	ref double[] WORK,
	int offset_work
)
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Parameters

NORM  String
(input) CHARACTER*1 Specifies the value to be returned in DLANSY as described above.
UPLO  String
(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  Int32
(input) INTEGER The order of the matrix A. N .GE. 0. When N = 0, DLANSY is set to zero.
A  Double
(input) DOUBLE PRECISION 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.
offset_a  Int32
 
LDA  Int32
(input) INTEGER The leading dimension of the array A. LDA .GE. max(N,1).
WORK  Double
(workspace) DOUBLE PRECISION array, dimension (MAX(1,LWORK)), where LWORK .GE. N when NORM = 'I' or '1' or 'O'; otherwise, WORK is not referenced.
offset_work  Int32
 

Return Value

Double
See Also