/src/igraph/vendor/lapack/daxpy.c
Line | Count | Source (jump to first uncovered line) |
1 | | /* -- translated by f2c (version 20191129). |
2 | | You must link the resulting object file with libf2c: |
3 | | on Microsoft Windows system, link with libf2c.lib; |
4 | | on Linux or Unix systems, link with .../path/to/libf2c.a -lm |
5 | | or, if you install libf2c.a in a standard place, with -lf2c -lm |
6 | | -- in that order, at the end of the command line, as in |
7 | | cc *.o -lf2c -lm |
8 | | Source for libf2c is in /netlib/f2c/libf2c.zip, e.g., |
9 | | |
10 | | http://www.netlib.org/f2c/libf2c.zip |
11 | | */ |
12 | | |
13 | | #include "f2c.h" |
14 | | |
15 | | /* > \brief \b DAXPY |
16 | | |
17 | | =========== DOCUMENTATION =========== |
18 | | |
19 | | Online html documentation available at |
20 | | http://www.netlib.org/lapack/explore-html/ |
21 | | |
22 | | Definition: |
23 | | =========== |
24 | | |
25 | | SUBROUTINE DAXPY(N,DA,DX,INCX,DY,INCY) |
26 | | |
27 | | DOUBLE PRECISION DA |
28 | | INTEGER INCX,INCY,N |
29 | | DOUBLE PRECISION DX(*),DY(*) |
30 | | |
31 | | |
32 | | > \par Purpose: |
33 | | ============= |
34 | | > |
35 | | > \verbatim |
36 | | > |
37 | | > DAXPY constant times a vector plus a vector. |
38 | | > uses unrolled loops for increments equal to one. |
39 | | > \endverbatim |
40 | | |
41 | | Arguments: |
42 | | ========== |
43 | | |
44 | | > \param[in] N |
45 | | > \verbatim |
46 | | > N is INTEGER |
47 | | > number of elements in input vector(s) |
48 | | > \endverbatim |
49 | | > |
50 | | > \param[in] DA |
51 | | > \verbatim |
52 | | > DA is DOUBLE PRECISION |
53 | | > On entry, DA specifies the scalar alpha. |
54 | | > \endverbatim |
55 | | > |
56 | | > \param[in] DX |
57 | | > \verbatim |
58 | | > DX is DOUBLE PRECISION array, dimension ( 1 + ( N - 1 )*abs( INCX ) ) |
59 | | > \endverbatim |
60 | | > |
61 | | > \param[in] INCX |
62 | | > \verbatim |
63 | | > INCX is INTEGER |
64 | | > storage spacing between elements of DX |
65 | | > \endverbatim |
66 | | > |
67 | | > \param[in,out] DY |
68 | | > \verbatim |
69 | | > DY is DOUBLE PRECISION array, dimension ( 1 + ( N - 1 )*abs( INCY ) ) |
70 | | > \endverbatim |
71 | | > |
72 | | > \param[in] INCY |
73 | | > \verbatim |
74 | | > INCY is INTEGER |
75 | | > storage spacing between elements of DY |
76 | | > \endverbatim |
77 | | |
78 | | Authors: |
79 | | ======== |
80 | | |
81 | | > \author Univ. of Tennessee |
82 | | > \author Univ. of California Berkeley |
83 | | > \author Univ. of Colorado Denver |
84 | | > \author NAG Ltd. |
85 | | |
86 | | > \date November 2017 |
87 | | |
88 | | > \ingroup double_blas_level1 |
89 | | |
90 | | > \par Further Details: |
91 | | ===================== |
92 | | > |
93 | | > \verbatim |
94 | | > |
95 | | > jack dongarra, linpack, 3/11/78. |
96 | | > modified 12/3/93, array(1) declarations changed to array(*) |
97 | | > \endverbatim |
98 | | > |
99 | | ===================================================================== |
100 | | Subroutine */ int igraphdaxpy_(integer *n, doublereal *da, doublereal *dx, |
101 | | integer *incx, doublereal *dy, integer *incy) |
102 | 0 | { |
103 | | /* System generated locals */ |
104 | 0 | integer i__1; |
105 | | |
106 | | /* Local variables */ |
107 | 0 | integer i__, m, ix, iy, mp1; |
108 | | |
109 | | |
110 | | /* -- Reference BLAS level1 routine (version 3.8.0) -- |
111 | | -- Reference BLAS is a software package provided by Univ. of Tennessee, -- |
112 | | -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- |
113 | | November 2017 |
114 | | |
115 | | |
116 | | ===================================================================== |
117 | | |
118 | | Parameter adjustments */ |
119 | 0 | --dy; |
120 | 0 | --dx; |
121 | | |
122 | | /* Function Body */ |
123 | 0 | if (*n <= 0) { |
124 | 0 | return 0; |
125 | 0 | } |
126 | 0 | if (*da == 0.) { |
127 | 0 | return 0; |
128 | 0 | } |
129 | 0 | if (*incx == 1 && *incy == 1) { |
130 | | |
131 | | /* code for both increments equal to 1 |
132 | | |
133 | | |
134 | | clean-up loop */ |
135 | |
|
136 | 0 | m = *n % 4; |
137 | 0 | if (m != 0) { |
138 | 0 | i__1 = m; |
139 | 0 | for (i__ = 1; i__ <= i__1; ++i__) { |
140 | 0 | dy[i__] += *da * dx[i__]; |
141 | 0 | } |
142 | 0 | } |
143 | 0 | if (*n < 4) { |
144 | 0 | return 0; |
145 | 0 | } |
146 | 0 | mp1 = m + 1; |
147 | 0 | i__1 = *n; |
148 | 0 | for (i__ = mp1; i__ <= i__1; i__ += 4) { |
149 | 0 | dy[i__] += *da * dx[i__]; |
150 | 0 | dy[i__ + 1] += *da * dx[i__ + 1]; |
151 | 0 | dy[i__ + 2] += *da * dx[i__ + 2]; |
152 | 0 | dy[i__ + 3] += *da * dx[i__ + 3]; |
153 | 0 | } |
154 | 0 | } else { |
155 | | |
156 | | /* code for unequal increments or equal increments |
157 | | not equal to 1 */ |
158 | |
|
159 | 0 | ix = 1; |
160 | 0 | iy = 1; |
161 | 0 | if (*incx < 0) { |
162 | 0 | ix = (-(*n) + 1) * *incx + 1; |
163 | 0 | } |
164 | 0 | if (*incy < 0) { |
165 | 0 | iy = (-(*n) + 1) * *incy + 1; |
166 | 0 | } |
167 | 0 | i__1 = *n; |
168 | 0 | for (i__ = 1; i__ <= i__1; ++i__) { |
169 | 0 | dy[iy] += *da * dx[ix]; |
170 | 0 | ix += *incx; |
171 | 0 | iy += *incy; |
172 | 0 | } |
173 | 0 | } |
174 | 0 | return 0; |
175 | 0 | } /* igraphdaxpy_ */ |
176 | | |