LAPACK  3.10.0
LAPACK: Linear Algebra PACKage
zdotc.f
Go to the documentation of this file.
1 *> \brief \b ZDOTC
2 *
3 * =========== DOCUMENTATION ===========
4 *
5 * Online html documentation available at
6 * http://www.netlib.org/lapack/explore-html/
7 *
8 * Definition:
9 * ===========
10 *
11 * COMPLEX*16 FUNCTION ZDOTC(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 *> ZDOTC forms the dot product of two complex vectors
27 *> ZDOTC = X^H * Y
28 *>
29 *> \endverbatim
30 *
31 * Arguments:
32 * ==========
33 *
34 *> \param[in] N
35 *> \verbatim
36 *> N is INTEGER
37 *> number of elements in input vector(s)
38 *> \endverbatim
39 *>
40 *> \param[in] ZX
41 *> \verbatim
42 *> ZX is COMPLEX*16 array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
43 *> \endverbatim
44 *>
45 *> \param[in] INCX
46 *> \verbatim
47 *> INCX is INTEGER
48 *> storage spacing between elements of ZX
49 *> \endverbatim
50 *>
51 *> \param[in] ZY
52 *> \verbatim
53 *> ZY is COMPLEX*16 array, dimension ( 1 + ( N - 1 )*abs( INCY ) )
54 *> \endverbatim
55 *>
56 *> \param[in] INCY
57 *> \verbatim
58 *> INCY is INTEGER
59 *> storage spacing between elements of ZY
60 *> \endverbatim
61 *
62 * Authors:
63 * ========
64 *
65 *> \author Univ. of Tennessee
66 *> \author Univ. of California Berkeley
67 *> \author Univ. of Colorado Denver
68 *> \author NAG Ltd.
69 *
70 *> \ingroup complex16_blas_level1
71 *
72 *> \par Further Details:
73 * =====================
74 *>
75 *> \verbatim
76 *>
77 *> jack dongarra, 3/11/78.
78 *> modified 12/3/93, array(1) declarations changed to array(*)
79 *> \endverbatim
80 *>
81 * =====================================================================
82  COMPLEX*16 FUNCTION zdotc(N,ZX,INCX,ZY,INCY)
83 *
84 * -- Reference BLAS level1 routine --
85 * -- Reference BLAS is a software package provided by Univ. of Tennessee, --
86 * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
87 *
88 * .. Scalar Arguments ..
89  INTEGER incx,incy,n
90 * ..
91 * .. Array Arguments ..
92  COMPLEX*16 zx(*),zy(*)
93 * ..
94 *
95 * =====================================================================
96 *
97 * .. Local Scalars ..
98  COMPLEX*16 ztemp
99  INTEGER i,ix,iy
100 * ..
101 * .. Intrinsic Functions ..
102  INTRINSIC dconjg
103 * ..
104  ztemp = (0.0d0,0.0d0)
105  zdotc = (0.0d0,0.0d0)
106  IF (n.LE.0) RETURN
107  IF (incx.EQ.1 .AND. incy.EQ.1) THEN
108 *
109 * code for both increments equal to 1
110 *
111  DO i = 1,n
112  ztemp = ztemp + dconjg(zx(i))*zy(i)
113  END DO
114  ELSE
115 *
116 * code for unequal increments or equal increments
117 * not equal to 1
118 *
119  ix = 1
120  iy = 1
121  IF (incx.LT.0) ix = (-n+1)*incx + 1
122  IF (incy.LT.0) iy = (-n+1)*incy + 1
123  DO i = 1,n
124  ztemp = ztemp + dconjg(zx(ix))*zy(iy)
125  ix = ix + incx
126  iy = iy + incy
127  END DO
128  END IF
129  zdotc = ztemp
130  RETURN
131 *
132 * End of ZDOTC
133 *
134  END
complex *16 function zdotc(N, ZX, INCX, ZY, INCY)
ZDOTC
Definition: zdotc.f:83