Return to dcopy.f CVS log

Up to [local] / rpl / lapack / blas

En route pour la 4.0.15 !

    1:       SUBROUTINE DCOPY(N,DX,INCX,DY,INCY)
    2: *     .. Scalar Arguments ..
    3:       INTEGER INCX,INCY,N
    4: *     ..
    5: *     .. Array Arguments ..
    6:       DOUBLE PRECISION DX(*),DY(*)
    7: *     ..
    8: *
    9: *  Purpose
   10: *  =======
   11: *
   12: *     DCOPY copies a vector, x, to a vector, y.
   13: *     uses unrolled loops for increments equal to one.
   14: *
   15: *  Further Details
   16: *  ===============
   17: *
   18: *     jack dongarra, linpack, 3/11/78.
   19: *     modified 12/3/93, array(1) declarations changed to array(*)
   20: *
   21: *  =====================================================================
   22: *
   23: *     .. Local Scalars ..
   24:       INTEGER I,IX,IY,M,MP1
   25: *     ..
   26: *     .. Intrinsic Functions ..
   27:       INTRINSIC MOD
   28: *     ..
   29:       IF (N.LE.0) RETURN
   30:       IF (INCX.EQ.1 .AND. INCY.EQ.1) GO TO 20
   31: *
   32: *        code for unequal increments or equal increments
   33: *          not equal to 1
   34: *
   35:       IX = 1
   36:       IY = 1
   37:       IF (INCX.LT.0) IX = (-N+1)*INCX + 1
   38:       IF (INCY.LT.0) IY = (-N+1)*INCY + 1
   39:       DO 10 I = 1,N
   40:           DY(IY) = DX(IX)
   41:           IX = IX + INCX
   42:           IY = IY + INCY
   43:    10 CONTINUE
   44:       RETURN
   45: *
   46: *        code for both increments equal to 1
   47: *
   48: *
   49: *        clean-up loop
   50: *
   51:    20 M = MOD(N,7)
   52:       IF (M.EQ.0) GO TO 40
   53:       DO 30 I = 1,M
   54:           DY(I) = DX(I)
   55:    30 CONTINUE
   56:       IF (N.LT.7) RETURN
   57:    40 MP1 = M + 1
   58:       DO 50 I = MP1,N,7
   59:           DY(I) = DX(I)
   60:           DY(I+1) = DX(I+1)
   61:           DY(I+2) = DX(I+2)
   62:           DY(I+3) = DX(I+3)
   63:           DY(I+4) = DX(I+4)
   64:           DY(I+5) = DX(I+5)
   65:           DY(I+6) = DX(I+6)
   66:    50 CONTINUE
   67:       RETURN
   68:       END