SLAPTM multiplies an N by NRHS matrix X by a symmetric tridiagonal


 matrix A and stores the result in a matrix B.  The operation has the


 form


    B := alpha * A * X + beta * B


 where alpha may be either 1. or -1. and beta may be 0., 1., or -1.

N

          N is INTEGER


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

NRHS

          NRHS is INTEGER


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


          of the matrices X and B.

ALPHA

          ALPHA is REAL


          The scalar alpha.  ALPHA must be 1. or -1.; otherwise,


          it is assumed to be 0.

D

          D is REAL array, dimension (N)


          The n diagonal elements of the tridiagonal matrix A.

E

          E is REAL array, dimension (N-1)


          The (n-1) subdiagonal or superdiagonal elements of A.

X

          X is REAL array, dimension (LDX,NRHS)


          The N by NRHS matrix X.

LDX

          LDX is INTEGER


          The leading dimension of the array X.  LDX >= max(N,1).

BETA

          BETA is REAL


          The scalar beta.  BETA must be 0., 1., or -1.; otherwise,


          it is assumed to be 1.

B

          B is REAL array, dimension (LDB,NRHS)


          On entry, the N by NRHS matrix B.


          On exit, B is overwritten by the matrix expression


          B := alpha * A * X + beta * B.

LDB

          LDB is INTEGER


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

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