subroutine dscal	(	integer	N,
		double precision	DA,
		double precision, dimension(*)	DX,
		integer	INCX
	)

DSCAL

Purpose:

    DSCAL scales a vector by a constant.
    uses unrolled loops for increment equal to one.

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Date

December 2016

Further Details:

     jack dongarra, linpack, 3/11/78.
     modified 3/93 to return if incx .le. 0.
     modified 12/3/93, array(1) declarations changed to array(*)

Definition at line 55 of file dscal.f.

*
*  -- Reference BLAS level1 routine (version 3.7.0) --
*  -- Reference BLAS is a software package provided by Univ. of Tennessee,    --
*  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
*     December 2016
*
*     .. Scalar Arguments ..
      DOUBLE PRECISION da
      INTEGER incx,n
*     ..
*     .. Array Arguments ..
      DOUBLE PRECISION dx(*)
*     ..
*
*  =====================================================================
*
*     .. Local Scalars ..
      INTEGER i,m,mp1,nincx
*     ..
*     .. Intrinsic Functions ..
      INTRINSIC mod
*     ..
      IF (n.LE.0 .OR. incx.LE.0) RETURN
      IF (incx.EQ.1) THEN
*
*        code for increment equal to 1
*
*
*        clean-up loop
*
         m = mod(n,5)
         IF (m.NE.0) THEN
            DO i = 1,m
               dx(i) = da*dx(i)
            END DO
            IF (n.LT.5) RETURN
         END IF
         mp1 = m + 1
         DO 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)
         END DO
      ELSE
*
*        code for increment not equal to 1
*
         nincx = n*incx
         DO i = 1,nincx,incx
            dx(i) = da*dx(i)
         END DO
      END IF
      RETURN