zlagsy()

subroutine zlagsy	(	integer	N,
		integer	K,
		double precision, dimension( * )	D,
		complex*16, dimension( lda, * )	A,
		integer	LDA,
		integer, dimension( 4 )	ISEED,
		complex*16, dimension( * )	WORK,
		integer	INFO
	)

ZLAGSY

Purpose:

 ZLAGSY 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.

Parameters

[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 DOUBLE PRECISION array, dimension (N) The diagonal elements of the diagonal matrix D.
[out]	A	A is COMPLEX*16 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*16 array, dimension (2*N)
[out]	INFO	INFO is INTEGER = 0: successful exit < 0: if INFO = -i, the i-th argument had an illegal value

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.