###
Compute norms of a real skew-symmetric matrix

**[Specification]**
**[Arguments]**
**[Method]**
**[References]**
**[Comments]**
**[Example]**
**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 real skew-symmetric matrix.
Note that for this kind of matrices the infinity norm is equal
to the one norm.

**Specification**
DOUBLE PRECISION FUNCTION MA02MD( NORM, UPLO, N, A, LDA, DWORK )
C .. Scalar Arguments ..
CHARACTER NORM, UPLO
INTEGER LDA, N
C .. Array Arguments ..
DOUBLE PRECISION A( LDA, * ), DWORK( * )

**Function Value**
MA02MD DOUBLE PRECISION
The computed norm.

**Arguments**
**Mode Parameters**

NORM CHARACTER*1
Specifies the value to be returned in MA02MD:
= '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-symmetric 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, MA02MD is
set to zero.
A (input) DOUBLE PRECISION array, dimension (LDA,N)
The skew-symmetric matrix A. If UPLO = 'U', the leading
N-by-N strictly upper triangular part of A contains the
strictly upper triangular part of the matrix A, and the
lower triangular part of A is not referenced.
If UPLO = 'L', the leading N-by-N strictly lower
triangular part of A contains the strictly lower
triangular part of the matrix A, and the upper triangular
part of A is not referenced.
The diagonal of A need not be set to 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**
None

**Example**
**Program Text**

None

**Program Data**
None

**Program Results**
None

**Return to Supporting Routines index**