Purpose
To compute the value of the one norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a complex skew-Hermitian matrix. Note that for this kind of matrices the infinity norm is equal to the one norm.Specification
DOUBLE PRECISION FUNCTION MA02MZ( NORM, UPLO, N, A, LDA, DWORK )
C .. Scalar Arguments ..
CHARACTER NORM, UPLO
INTEGER LDA, N
C .. Array Arguments ..
DOUBLE PRECISION DWORK( * )
COMPLEX*16 A( LDA, * )
Function Value
MA02MZ DOUBLE PRECISION
The computed norm.
Arguments
Mode Parameters
NORM CHARACTER*1
Specifies the value to be returned in MA02MZ:
= '1' or 'O': one norm of A;
= 'F' or 'E': Frobenius norm of A;
= 'I': infinity norm of A;
= 'M': max(abs(A(i,j)).
UPLO CHARACTER*1
Specifies whether the upper or lower triangular part of
the skew-Hermitian matrix A is to be referenced.
= 'U': Upper triangular part of A is referenced;
= 'L': Lower triangular part of A is referenced.
Input/Output Parameters
N (input) INTEGER
The order of the matrix A. N >= 0. When N = 0, MA02MZ is
set to zero.
A (input) COMPLEX*16 array, dimension (LDA,N)
The skew-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 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 real parts of the diagonal elements of A need not be
set and are assumed to be zero.
LDA INTEGER
The leading dimension of the array A. LDA >= max(1,N).
Workspace
DWORK DOUBLE PRECISION array, dimension (MAX(1,LDWORK)),
where LDWORK >= N when NORM = 'I' or '1' or 'O';
otherwise, DWORK is not referenced.
Further Comments
NoneExample
Program Text
NoneProgram Data
NoneProgram Results
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