```01:       SUBROUTINE ZCOPY(N,ZX,INCX,ZY,INCY)
02: *     .. Scalar Arguments ..
03:       INTEGER INCX,INCY,N
04: *     ..
05: *     .. Array Arguments ..
06:       DOUBLE COMPLEX ZX(*),ZY(*)
07: *     ..
08: *
09: *  Purpose
10: *  =======
11: *
12: *     ZCOPY copies a vector, x, to a vector, y.
13: *
14: *  Further Details
15: *  ===============
16: *
17: *     jack dongarra, linpack, 4/11/78.
18: *     modified 12/3/93, array(1) declarations changed to array(*)
19: *
20: *  =====================================================================
21: *
22: *     .. Local Scalars ..
23:       INTEGER I,IX,IY
24: *     ..
25:       IF (N.LE.0) RETURN
26:       IF (INCX.EQ.1 .AND. INCY.EQ.1) GO TO 20
27: *
28: *        code for unequal increments or equal increments
29: *          not equal to 1
30: *
31:       IX = 1
32:       IY = 1
33:       IF (INCX.LT.0) IX = (-N+1)*INCX + 1
34:       IF (INCY.LT.0) IY = (-N+1)*INCY + 1
35:       DO 10 I = 1,N
36:           ZY(IY) = ZX(IX)
37:           IX = IX + INCX
38:           IY = IY + INCY
39:    10 CONTINUE
40:       RETURN
41: *
42: *        code for both increments equal to 1
43: *
44:    20 DO 30 I = 1,N
45:           ZY(I) = ZX(I)
46:    30 CONTINUE
47:       RETURN
48:       END
49: ```