2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 2019-2020 The DragonFly Project. All rights reserved.
6 * This code is derived from software contributed to The DragonFly Project
7 * by Aaron LI <aly@aaronly.me>
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in
17 * the documentation and/or other materials provided with the
19 * 3. Neither the name of The DragonFly Project nor the names of its
20 * contributors may be used to endorse or promote products derived
21 * from this software without specific, prior written permission.
23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
24 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
26 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
27 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
28 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
29 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
30 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
31 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
32 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
33 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
49 date_set(struct date *date, int y, int m, int d)
57 double latitude; /* degree */
58 double longitude; /* degree */
59 double elevation; /* meter */
60 double zone; /* time offset (in days) from UTC */
73 int dayofweek_from_fixed(int rd);
74 int kday_after(int dow, int rd);
75 int kday_nearest(int dow, int rd);
76 int kday_onbefore(int dow, int rd);
77 int nth_kday(int n, int dow, struct date *date);
78 int dayofyear_from_fixed(int rd);
80 double julian_centuries(double t);
81 double sidereal_from_moment(double t);
83 double ephemeris_correction(double t);
84 double universal_from_dynamical(double t);
85 double dynamical_from_universal(double t);
87 double equation_of_time(double t);
88 double apparent_from_local(double t, double longitude);
89 double local_from_apparent(double t, double longitude);
91 double obliquity(double t);
92 double declination(double t, double beta, double lambda);
93 double right_ascension(double t, double beta, double lambda);
95 double refraction(double elevation);
97 int format_time(char *buf, size_t size, double t);
98 int format_zone(char *buf, size_t size, double zone);
99 int format_location(char *buf, size_t size, const struct location *loc);