![]() |
LAPACK
3.7.0
LAPACK: Linear Algebra PACKage
|
subroutine clagsy | ( | integer | N, |
integer | K, | ||
real, dimension( * ) | D, | ||
complex, dimension( lda, * ) | A, | ||
integer | LDA, | ||
integer, dimension( 4 ) | ISEED, | ||
complex, dimension( * ) | WORK, | ||
integer | INFO | ||
) |
CLAGSY
CLAGSY generates a complex symmetric matrix A, by pre- and post- multiplying a real diagonal matrix D with a random unitary matrix: A = U*D*U**T. The semi-bandwidth may then be reduced to k by additional unitary transformations.
[in] | N | N is INTEGER The order of the matrix A. N >= 0. |
[in] | K | K is INTEGER The number of nonzero subdiagonals within the band of A. 0 <= K <= N-1. |
[in] | D | D is REAL array, dimension (N) The diagonal elements of the diagonal matrix D. |
[out] | A | A is COMPLEX array, dimension (LDA,N) The generated n by n symmetric matrix A (the full matrix is stored). |
[in] | LDA | LDA is INTEGER The leading dimension of the array A. LDA >= N. |
[in,out] | ISEED | ISEED is INTEGER array, dimension (4) On entry, the seed of the random number generator; the array elements must be between 0 and 4095, and ISEED(4) must be odd. On exit, the seed is updated. |
[out] | WORK | WORK is COMPLEX array, dimension (2*N) |
[out] | INFO | INFO is INTEGER = 0: successful exit < 0: if INFO = -i, the i-th argument had an illegal value |
Definition at line 104 of file clagsy.f.