CLATSP
Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
November 2006
November 2006
Purpose
CLATSP generates a special test matrix for the complex symmetric
(indefinite) factorization for packed matrices. The pivot blocks of
the generated matrix will be in the following order:
2x2 pivot block, non diagonalizable
1x1 pivot block
2x2 pivot block, diagonalizable
(cycle repeats)
A row interchange is required for each non-diagonalizable 2x2 block.
(indefinite) factorization for packed matrices. The pivot blocks of
the generated matrix will be in the following order:
2x2 pivot block, non diagonalizable
1x1 pivot block
2x2 pivot block, diagonalizable
(cycle repeats)
A row interchange is required for each non-diagonalizable 2x2 block.
Arguments
| UPLO |
(input) CHARACTER
Specifies whether the generated matrix is to be upper or
lower triangular. = 'U': Upper triangular = 'L': Lower triangular |
| N |
(input) INTEGER
The dimension of the matrix to be generated.
|
| X |
(output) COMPLEX array, dimension (N*(N+1)/2)
The generated matrix in packed storage format. The matrix
consists of 3x3 and 2x2 diagonal blocks which result in the pivot sequence given above. The matrix outside these diagonal blocks is zero. |
| ISEED |
(input/output) INTEGER array, dimension (4)
On entry, the seed for the random number generator. The last
of the four integers must be odd. (modified on exit) |