slagsy.f3

!>
!> 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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