LAPACK 3.3.1 Linear Algebra PACKage

# scopy.f

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```00001       SUBROUTINE SCOPY(N,SX,INCX,SY,INCY)
00002 *     .. Scalar Arguments ..
00003       INTEGER INCX,INCY,N
00004 *     ..
00005 *     .. Array Arguments ..
00006       REAL SX(*),SY(*)
00007 *     ..
00008 *
00009 *  Purpose
00010 *  =======
00011 *
00012 *     SCOPY copies a vector, x, to a vector, y.
00013 *     uses unrolled loops for increments equal to 1.
00014 *
00015 *  Further Details
00016 *  ===============
00017 *
00018 *     jack dongarra, linpack, 3/11/78.
00019 *     modified 12/3/93, array(1) declarations changed to array(*)
00020 *
00021 *  =====================================================================
00022 *
00023 *     .. Local Scalars ..
00024       INTEGER I,IX,IY,M,MP1
00025 *     ..
00026 *     .. Intrinsic Functions ..
00027       INTRINSIC MOD
00028 *     ..
00029       IF (N.LE.0) RETURN
00030       IF (INCX.EQ.1 .AND. INCY.EQ.1) THEN
00031 *
00032 *        code for both increments equal to 1
00033 *
00034 *
00035 *        clean-up loop
00036 *
00037          M = MOD(N,7)
00038          IF (M.NE.0) THEN
00039             DO I = 1,M
00040                SY(I) = SX(I)
00041             END DO
00042             IF (N.LT.7) RETURN
00043          END IF
00044          MP1 = M + 1
00045          DO I = MP1,N,7
00046             SY(I) = SX(I)
00047             SY(I+1) = SX(I+1)
00048             SY(I+2) = SX(I+2)
00049             SY(I+3) = SX(I+3)
00050             SY(I+4) = SX(I+4)
00051             SY(I+5) = SX(I+5)
00052             SY(I+6) = SX(I+6)
00053          END DO
00054       ELSE
00055 *
00056 *        code for unequal increments or equal increments
00057 *          not equal to 1
00058 *
00059          IX = 1
00060          IY = 1
00061          IF (INCX.LT.0) IX = (-N+1)*INCX + 1
00062          IF (INCY.LT.0) IY = (-N+1)*INCY + 1
00063          DO I = 1,N
00064             SY(IY) = SX(IX)
00065             IX = IX + INCX
00066             IY = IY + INCY
00067          END DO
00068       END IF
00069       RETURN
00070       END
```