SLAGSY generates a real symmetric matrix A, by pre- and post-


 multiplying a real diagonal matrix D with a random orthogonal matrix:


 A = U*D*U'. The semi-bandwidth may then be reduced to k by additional


 orthogonal transformations.

N

          N is INTEGER


          The order of the matrix A.  N >= 0.

K

          K is INTEGER


          The number of nonzero subdiagonals within the band of A.


          0 <= K <= N-1.

D

          D is REAL array, dimension (N)


          The diagonal elements of the diagonal matrix D.

A

          A is REAL array, dimension (LDA,N)


          The generated n by n symmetric matrix A (the full matrix is


          stored).

LDA

          LDA is INTEGER


          The leading dimension of the array A.  LDA >= N.

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.

WORK

          WORK is REAL array, dimension (2*N)

INFO

          INFO is INTEGER


          = 0: successful exit


          < 0: if INFO = -i, the i-th argument had an illegal value

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