1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
|
/* Ergo, version 3.8, a program for linear scaling electronic structure
* calculations.
* Copyright (C) 2019 Elias Rudberg, Emanuel H. Rubensson, Pawel Salek,
* and Anastasia Kruchinina.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* Primary academic reference:
* Ergo: An open-source program for linear-scaling electronic structure
* calculations,
* Elias Rudberg, Emanuel H. Rubensson, Pawel Salek, and Anastasia
* Kruchinina,
* SoftwareX 7, 107 (2018),
* <http://dx.doi.org/10.1016/j.softx.2018.03.005>
*
* For further information about Ergo, see <http://www.ergoscf.org>.
*/
/* This file belongs to the template_lapack part of the Ergo source
* code. The source files in the template_lapack directory are modified
* versions of files originally distributed as CLAPACK, see the
* Copyright/license notice in the file template_lapack/COPYING.
*/
#ifndef TEMPLATE_BLAS_SYR2_HEADER
#define TEMPLATE_BLAS_SYR2_HEADER
template<class Treal>
int template_blas_syr2(const char *uplo, const integer *n, const Treal *alpha,
const Treal *x, const integer *incx, const Treal *y, const integer *incy,
Treal *a, const integer *lda)
{
/* System generated locals */
integer a_dim1, a_offset, i__1, i__2;
/* Local variables */
integer info;
Treal temp1, temp2;
integer i__, j;
integer ix, iy, jx, jy, kx, ky;
#define a_ref(a_1,a_2) a[(a_2)*a_dim1 + a_1]
/* Purpose
=======
DSYR2 performs the symmetric rank 2 operation
A := alpha*x*y' + alpha*y*x' + A,
where alpha is a scalar, x and y are n element vectors and A is an n
by n symmetric matrix.
Parameters
==========
UPLO - CHARACTER*1.
On entry, UPLO specifies whether the upper or lower
triangular part of the array A is to be referenced as
follows:
UPLO = 'U' or 'u' Only the upper triangular part of A
is to be referenced.
UPLO = 'L' or 'l' Only the lower triangular part of A
is to be referenced.
Unchanged on exit.
N - INTEGER.
On entry, N specifies the order of the matrix A.
N must be at least zero.
Unchanged on exit.
ALPHA - DOUBLE PRECISION.
On entry, ALPHA specifies the scalar alpha.
Unchanged on exit.
X - DOUBLE PRECISION array of dimension at least
( 1 + ( n - 1 )*abs( INCX ) ).
Before entry, the incremented array X must contain the n
element vector x.
Unchanged on exit.
INCX - INTEGER.
On entry, INCX specifies the increment for the elements of
X. INCX must not be zero.
Unchanged on exit.
Y - DOUBLE PRECISION array of dimension at least
( 1 + ( n - 1 )*abs( INCY ) ).
Before entry, the incremented array Y must contain the n
element vector y.
Unchanged on exit.
INCY - INTEGER.
On entry, INCY specifies the increment for the elements of
Y. INCY must not be zero.
Unchanged on exit.
A - DOUBLE PRECISION array of DIMENSION ( LDA, n ).
Before entry with UPLO = 'U' or 'u', the leading n by n
upper triangular part of the array A must contain the upper
triangular part of the symmetric matrix and the strictly
lower triangular part of A is not referenced. On exit, the
upper triangular part of the array A is overwritten by the
upper triangular part of the updated matrix.
Before entry with UPLO = 'L' or 'l', the leading n by n
lower triangular part of the array A must contain the lower
triangular part of the symmetric matrix and the strictly
upper triangular part of A is not referenced. On exit, the
lower triangular part of the array A is overwritten by the
lower triangular part of the updated matrix.
LDA - INTEGER.
On entry, LDA specifies the first dimension of A as declared
in the calling (sub) program. LDA must be at least
max( 1, n ).
Unchanged on exit.
Level 2 Blas routine.
-- Written on 22-October-1986.
Jack Dongarra, Argonne National Lab.
Jeremy Du Croz, Nag Central Office.
Sven Hammarling, Nag Central Office.
Richard Hanson, Sandia National Labs.
Test the input parameters.
Parameter adjustments */
--x;
--y;
a_dim1 = *lda;
a_offset = 1 + a_dim1 * 1;
a -= a_offset;
/* Initialization added by Elias to get rid of compiler warnings. */
jx = jy = kx = ky = 0;
/* Function Body */
info = 0;
if (! template_blas_lsame(uplo, "U") && ! template_blas_lsame(uplo, "L")) {
info = 1;
} else if (*n < 0) {
info = 2;
} else if (*incx == 0) {
info = 5;
} else if (*incy == 0) {
info = 7;
} else if (*lda < maxMACRO(1,*n)) {
info = 9;
}
if (info != 0) {
template_blas_erbla("SYR2 ", &info);
return 0;
}
/* Quick return if possible. */
if (*n == 0 || *alpha == 0.) {
return 0;
}
/* Set up the start points in X and Y if the increments are not both
unity. */
if (*incx != 1 || *incy != 1) {
if (*incx > 0) {
kx = 1;
} else {
kx = 1 - (*n - 1) * *incx;
}
if (*incy > 0) {
ky = 1;
} else {
ky = 1 - (*n - 1) * *incy;
}
jx = kx;
jy = ky;
}
/* Start the operations. In this version the elements of A are
accessed sequentially with one pass through the triangular part
of A. */
if (template_blas_lsame(uplo, "U")) {
/* Form A when A is stored in the upper triangle. */
if (*incx == 1 && *incy == 1) {
i__1 = *n;
for (j = 1; j <= i__1; ++j) {
if (x[j] != 0. || y[j] != 0.) {
temp1 = *alpha * y[j];
temp2 = *alpha * x[j];
i__2 = j;
for (i__ = 1; i__ <= i__2; ++i__) {
a_ref(i__, j) = a_ref(i__, j) + x[i__] * temp1 + y[
i__] * temp2;
/* L10: */
}
}
/* L20: */
}
} else {
i__1 = *n;
for (j = 1; j <= i__1; ++j) {
if (x[jx] != 0. || y[jy] != 0.) {
temp1 = *alpha * y[jy];
temp2 = *alpha * x[jx];
ix = kx;
iy = ky;
i__2 = j;
for (i__ = 1; i__ <= i__2; ++i__) {
a_ref(i__, j) = a_ref(i__, j) + x[ix] * temp1 + y[iy]
* temp2;
ix += *incx;
iy += *incy;
/* L30: */
}
}
jx += *incx;
jy += *incy;
/* L40: */
}
}
} else {
/* Form A when A is stored in the lower triangle. */
if (*incx == 1 && *incy == 1) {
i__1 = *n;
for (j = 1; j <= i__1; ++j) {
if (x[j] != 0. || y[j] != 0.) {
temp1 = *alpha * y[j];
temp2 = *alpha * x[j];
i__2 = *n;
for (i__ = j; i__ <= i__2; ++i__) {
a_ref(i__, j) = a_ref(i__, j) + x[i__] * temp1 + y[
i__] * temp2;
/* L50: */
}
}
/* L60: */
}
} else {
i__1 = *n;
for (j = 1; j <= i__1; ++j) {
if (x[jx] != 0. || y[jy] != 0.) {
temp1 = *alpha * y[jy];
temp2 = *alpha * x[jx];
ix = jx;
iy = jy;
i__2 = *n;
for (i__ = j; i__ <= i__2; ++i__) {
a_ref(i__, j) = a_ref(i__, j) + x[ix] * temp1 + y[iy]
* temp2;
ix += *incx;
iy += *incy;
/* L70: */
}
}
jx += *incx;
jy += *incy;
/* L80: */
}
}
}
return 0;
/* End of DSYR2 . */
} /* dsyr2_ */
#undef a_ref
#endif
|
