LAPACK  3.10.0
LAPACK: Linear Algebra PACKage
zdscal.f
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1 *> \brief \b ZDSCAL
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 ZDSCAL(N,DA,ZX,INCX)
12 *
13 * .. Scalar Arguments ..
14 * DOUBLE PRECISION DA
15 * INTEGER INCX,N
16 * ..
17 * .. Array Arguments ..
18 * COMPLEX*16 ZX(*)
19 * ..
20 *
21 *
22 *> \par Purpose:
23 * =============
24 *>
25 *> \verbatim
26 *>
27 *> ZDSCAL scales a vector by a constant.
28 *> \endverbatim
29 *
30 * Arguments:
31 * ==========
32 *
33 *> \param[in] N
34 *> \verbatim
35 *> N is INTEGER
36 *> number of elements in input vector(s)
37 *> \endverbatim
38 *>
39 *> \param[in] DA
40 *> \verbatim
41 *> DA is DOUBLE PRECISION
42 *> On entry, DA specifies the scalar alpha.
43 *> \endverbatim
44 *>
45 *> \param[in,out] ZX
46 *> \verbatim
47 *> ZX is COMPLEX*16 array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
48 *> \endverbatim
49 *>
50 *> \param[in] INCX
51 *> \verbatim
52 *> INCX is INTEGER
53 *> storage spacing between elements of ZX
54 *> \endverbatim
55 *
56 * Authors:
57 * ========
58 *
59 *> \author Univ. of Tennessee
60 *> \author Univ. of California Berkeley
61 *> \author Univ. of Colorado Denver
62 *> \author NAG Ltd.
63 *
64 *> \ingroup complex16_blas_level1
65 *
66 *> \par Further Details:
67 * =====================
68 *>
69 *> \verbatim
70 *>
71 *> jack dongarra, 3/11/78.
72 *> modified 3/93 to return if incx .le. 0.
73 *> modified 12/3/93, array(1) declarations changed to array(*)
74 *> \endverbatim
75 *>
76 * =====================================================================
77  SUBROUTINE zdscal(N,DA,ZX,INCX)
78 *
79 * -- Reference BLAS level1 routine --
80 * -- Reference BLAS is a software package provided by Univ. of Tennessee, --
81 * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
82 *
83 * .. Scalar Arguments ..
84  DOUBLE PRECISION DA
85  INTEGER INCX,N
86 * ..
87 * .. Array Arguments ..
88  COMPLEX*16 ZX(*)
89 * ..
90 *
91 * =====================================================================
92 *
93 * .. Local Scalars ..
94  INTEGER I,NINCX
95 * ..
96 * .. Intrinsic Functions ..
97  INTRINSIC dcmplx
98 * ..
99  IF (n.LE.0 .OR. incx.LE.0) RETURN
100  IF (incx.EQ.1) THEN
101 *
102 * code for increment equal to 1
103 *
104  DO i = 1,n
105  zx(i) = dcmplx(da,0.0d0)*zx(i)
106  END DO
107  ELSE
108 *
109 * code for increment not equal to 1
110 *
111  nincx = n*incx
112  DO i = 1,nincx,incx
113  zx(i) = dcmplx(da,0.0d0)*zx(i)
114  END DO
115  END IF
116  RETURN
117 *
118 * End of ZDSCAL
119 *
120  END
subroutine zdscal(N, DA, ZX, INCX)
ZDSCAL
Definition: zdscal.f:78