SLAVSP  performs one of the matrix-vector operations


    x := A*x  or  x := A'*x,


 where x is an N element vector and  A is one of the factors


 from the block U*D*U' or L*D*L' factorization computed by SSPTRF.


 If TRANS = 'N', multiplies by U  or U * D  (or L  or L * D)


 If TRANS = 'T', multiplies by U' or D * U' (or L' or D * L' )


 If TRANS = 'C', multiplies by U' or D * U' (or L' or D * L' )

UPLO

          UPLO is CHARACTER*1


          Specifies whether the factor stored in A is upper or lower


          triangular.


          = 'U':  Upper triangular


          = 'L':  Lower triangular

TRANS

          TRANS is CHARACTER*1


          Specifies the operation to be performed:


          = 'N':  x := A*x


          = 'T':  x := A'*x


          = 'C':  x := A'*x

DIAG

          DIAG is CHARACTER*1


          Specifies whether or not the diagonal blocks are unit


          matrices.  If the diagonal blocks are assumed to be unit,


          then A = U or A = L, otherwise A = U*D or A = L*D.


          = 'U':  Diagonal blocks are assumed to be unit matrices.


          = 'N':  Diagonal blocks are assumed to be non-unit matrices.

N

          N is INTEGER


          The number of rows and columns of the matrix A.  N >= 0.

NRHS

          NRHS is INTEGER


          The number of right hand sides, i.e., the number of vectors


          x to be multiplied by A.  NRHS >= 0.

A

          A is REAL array, dimension (N*(N+1)/2)


          The block diagonal matrix D and the multipliers used to


          obtain the factor U or L, stored as a packed triangular


          matrix as computed by SSPTRF.

IPIV

          IPIV is INTEGER array, dimension (N)


          The pivot indices from SSPTRF.

B

          B is REAL array, dimension (LDB,NRHS)


          On entry, B contains NRHS vectors of length N.


          On exit, B is overwritten with the product A * B.

LDB

          LDB is INTEGER


          The leading dimension of the array B.  LDB >= max(1,N).

INFO

          INFO is INTEGER


          = 0: successful exit


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

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