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SUBROUTINE SSCAL(N,SA,SX,INCX)
* .. Scalar Arguments ..
REAL SA
INTEGER INCX,N
* ..
* .. Array Arguments ..
REAL SX(*)
* ..
*
* Purpose
* =======
*
* scales a vector by a constant.
* uses unrolled loops for increment equal to 1.
* 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(*)
*
*
* .. Local Scalars ..
INTEGER I,M,MP1,NINCX
* ..
* .. Intrinsic Functions ..
INTRINSIC MOD
* ..
IF (N.LE.0 .OR. INCX.LE.0) RETURN
IF (INCX.EQ.1) GO TO 20
*
* code for increment not equal to 1
*
NINCX = N*INCX
DO 10 I = 1,NINCX,INCX
SX(I) = SA*SX(I)
10 CONTINUE
RETURN
*
* code for increment equal to 1
*
*
* clean-up loop
*
20 M = MOD(N,5)
IF (M.EQ.0) GO TO 40
DO 30 I = 1,M
SX(I) = SA*SX(I)
30 CONTINUE
IF (N.LT.5) RETURN
40 MP1 = M + 1
DO 50 I = MP1,N,5
SX(I) = SA*SX(I)
SX(I+1) = SA*SX(I+1)
SX(I+2) = SA*SX(I+2)
SX(I+3) = SA*SX(I+3)
SX(I+4) = SA*SX(I+4)
50 CONTINUE
RETURN
END
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