ergo
template_blas_basicmath.h
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1/* Ergo, version 3.8, a program for linear scaling electronic structure
2 * calculations.
3 * Copyright (C) 2019 Elias Rudberg, Emanuel H. Rubensson, Pawel Salek,
4 * and Anastasia Kruchinina.
5 *
6 * This program is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 3 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 *
19 * Primary academic reference:
20 * Ergo: An open-source program for linear-scaling electronic structure
21 * calculations,
22 * Elias Rudberg, Emanuel H. Rubensson, Pawel Salek, and Anastasia
23 * Kruchinina,
24 * SoftwareX 7, 107 (2018),
25 * <http://dx.doi.org/10.1016/j.softx.2018.03.005>
26 *
27 * For further information about Ergo, see <http://www.ergoscf.org>.
28 */
29
30 /* This file belongs to the template_lapack part of the Ergo source
31 * code. The source files in the template_lapack directory are modified
32 * versions of files originally distributed as CLAPACK, see the
33 * Copyright/license notice in the file template_lapack/COPYING.
34 */
35
36
37#ifndef TEMPLATE_BLAS_BASICMATH_HEADER
38#define TEMPLATE_BLAS_BASICMATH_HEADER
39
41
42template<class Treal>
43Treal template_blas_fabs(Treal x);
44
45template<class Treal>
46Treal template_blas_sqrt(Treal x);
47
48template<class Treal>
49Treal template_blas_exp(Treal x);
50
51template<class Treal>
52Treal template_blas_log(Treal x);
53
54template<class Treal>
55Treal template_blas_log10(Treal x);
56
57template<class Treal>
58Treal template_blas_erf(Treal x);
59
60template<class Treal>
61Treal template_blas_erfc(Treal x);
62
63template<class Treal>
64Treal template_blas_sin(Treal x);
65
66template<class Treal>
67Treal template_blas_cos(Treal x);
68
69template<class Treal>
70Treal template_blas_pow(Treal x, Treal y);
71
72
73/* template_blas_compute_pi_BBP
74 This routine computes the number pi up to the precision of Treal
75 using the BBP formula. */
76template<class Treal>
78{
79 Treal epsilon = template_blas_get_machine_epsilon<Treal>();
80 Treal one_over_16 = (Treal)1 / (Treal)16;
81 Treal one_over_16_to_pow_k = 1;
82 Treal sum = 0;
83 int k = 0;
84 do
85 {
86 Treal factor =
87 (Treal)4 / (Treal)(8*k + 1) -
88 (Treal)2 / (Treal)(8*k + 4) -
89 (Treal)1 / (Treal)(8*k + 5) -
90 (Treal)1 / (Treal)(8*k + 6);
91 sum += one_over_16_to_pow_k * factor;
92 k++;
93 one_over_16_to_pow_k *= one_over_16;
94 }
95 while(one_over_16_to_pow_k > epsilon);
96 return sum;
97}
98
99
100#endif
Treal template_blas_exp(Treal x)
Treal template_blas_sqrt(Treal x)
Treal template_blas_log(Treal x)
Treal template_blas_erf(Treal x)
Treal template_blas_cos(Treal x)
Treal template_blas_pow(Treal x, Treal y)
Treal template_blas_log10(Treal x)
Treal template_blas_fabs(Treal x)
Treal template_blas_erfc(Treal x)
Treal template_blas_compute_pi_BBP(Treal dummy)
Definition: template_blas_basicmath.h:77
Treal template_blas_sin(Treal x)