1: *> \brief \b ZSWAP
2: *
3: * =========== DOCUMENTATION ===========
4: *
5: * Online html documentation available at
6: * http://www.netlib.org/lapack/explore-html/
7: *
8: * Definition:
9: * ===========
10: *
11: * SUBROUTINE ZSWAP(N,ZX,INCX,ZY,INCY)
12: *
13: * .. Scalar Arguments ..
14: * INTEGER INCX,INCY,N
15: * ..
16: * .. Array Arguments ..
17: * COMPLEX*16 ZX(*),ZY(*)
18: * ..
19: *
20: *
21: *> \par Purpose:
22: * =============
23: *>
24: *> \verbatim
25: *>
26: *> ZSWAP interchanges two vectors.
27: *> \endverbatim
28: *
29: * Arguments:
30: * ==========
31: *
32: *> \param[in] N
33: *> \verbatim
34: *> N is INTEGER
35: *> number of elements in input vector(s)
36: *> \endverbatim
37: *>
38: *> \param[in,out] ZX
39: *> \verbatim
40: *> ZX is COMPLEX*16 array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
41: *> \endverbatim
42: *>
43: *> \param[in] INCX
44: *> \verbatim
45: *> INCX is INTEGER
46: *> storage spacing between elements of ZX
47: *> \endverbatim
48: *>
49: *> \param[in,out] ZY
50: *> \verbatim
51: *> ZY is COMPLEX*16 array, dimension ( 1 + ( N - 1 )*abs( INCY ) )
52: *> \endverbatim
53: *>
54: *> \param[in] INCY
55: *> \verbatim
56: *> INCY is INTEGER
57: *> storage spacing between elements of ZY
58: *> \endverbatim
59: *
60: * Authors:
61: * ========
62: *
63: *> \author Univ. of Tennessee
64: *> \author Univ. of California Berkeley
65: *> \author Univ. of Colorado Denver
66: *> \author NAG Ltd.
67: *
68: *> \ingroup complex16_blas_level1
69: *
70: *> \par Further Details:
71: * =====================
72: *>
73: *> \verbatim
74: *>
75: *> jack dongarra, 3/11/78.
76: *> modified 12/3/93, array(1) declarations changed to array(*)
77: *> \endverbatim
78: *>
79: * =====================================================================
80: SUBROUTINE ZSWAP(N,ZX,INCX,ZY,INCY)
81: *
82: * -- Reference BLAS level1 routine --
83: * -- Reference BLAS is a software package provided by Univ. of Tennessee, --
84: * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
85: *
86: * .. Scalar Arguments ..
87: INTEGER INCX,INCY,N
88: * ..
89: * .. Array Arguments ..
90: COMPLEX*16 ZX(*),ZY(*)
91: * ..
92: *
93: * =====================================================================
94: *
95: * .. Local Scalars ..
96: COMPLEX*16 ZTEMP
97: INTEGER I,IX,IY
98: * ..
99: IF (N.LE.0) RETURN
100: IF (INCX.EQ.1 .AND. INCY.EQ.1) THEN
101: *
102: * code for both increments equal to 1
103: DO I = 1,N
104: ZTEMP = ZX(I)
105: ZX(I) = ZY(I)
106: ZY(I) = ZTEMP
107: END DO
108: ELSE
109: *
110: * code for unequal increments or equal increments not equal
111: * to 1
112: *
113: IX = 1
114: IY = 1
115: IF (INCX.LT.0) IX = (-N+1)*INCX + 1
116: IF (INCY.LT.0) IY = (-N+1)*INCY + 1
117: DO I = 1,N
118: ZTEMP = ZX(IX)
119: ZX(IX) = ZY(IY)
120: ZY(IY) = ZTEMP
121: IX = IX + INCX
122: IY = IY + INCY
123: END DO
124: END IF
125: RETURN
126: *
127: * End of ZSWAP
128: *
129: END
CVSweb interface <joel.bertrand@systella.fr>