SUBROUTINE DSCAL(N,DA,DX,INCX)
DOUBLE PRECISION DA
INTEGER INCX,N
DOUBLE PRECISION DX(*)
INTEGER I,M,MP1,NINCX
INTRINSIC MOD
IF (N.LE.0 .OR. INCX.LE.0) RETURN
IF (INCX.EQ.1) GO TO 20
NINCX = N*INCX
DO 10 I = 1,NINCX,INCX
DX(I) = DA*DX(I)
10 CONTINUE
RETURN
20 M = MOD(N,5)
IF (M.EQ.0) GO TO 40
DO 30 I = 1,M
DX(I) = DA*DX(I)
30 CONTINUE
IF (N.LT.5) RETURN
40 MP1 = M + 1
DO 50 I = MP1,N,5
DX(I) = DA*DX(I)
DX(I+1) = DA*DX(I+1)
DX(I+2) = DA*DX(I+2)
DX(I+3) = DA*DX(I+3)
DX(I+4) = DA*DX(I+4)
50 CONTINUE
RETURN
END