/* This program is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 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, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. Copyright (C) 2003 Liam Girdwood <liam@gnova.org> A simple example showing some solar calculations. */ #include <stdio.h> #include <libnova/solar.h> #include <libnova/julian_day.h> #include <libnova/rise_set.h> #include <libnova/transform.h> void print_date (char * title, struct ln_zonedate* date) { printf ("\n%s\n",title); printf (" Year : %d\n", date->years); printf (" Month : %d\n", date->months); printf (" Day : %d\n", date->days); printf (" Hours : %d\n", date->hours); printf (" Minutes : %d\n", date->minutes); printf (" Seconds : %f\n", date->seconds); } int main (int argc, char * argv[]) { struct ln_equ_posn equ; struct ln_rst_time rst; struct ln_zonedate rise, set, transit; struct ln_lnlat_posn observer; struct ln_helio_posn pos; double JD; /* observers location (Edinburgh), used to calc rst */ observer.lat = 55.92; /* 55.92 N */ observer.lng = -3.18; /* 3.18 W */ /* get Julian day from local time */ JD = ln_get_julian_from_sys(); printf ("JD %f\n", JD); /* geometric coordinates */ ln_get_solar_geom_coords (JD, &pos); printf("Solar Coords longitude (deg) %f\n", pos.L); printf(" latitude (deg) %f\n", pos.B); printf(" radius vector (AU) %f\n", pos.R); /* ra, dec */ ln_get_solar_equ_coords (JD, &equ); printf("Solar Position RA %f\n", equ.ra); printf(" DEC %f\n", equ.dec); /* rise, set and transit */ if (ln_get_solar_rst (JD, &observer, &rst) == 1) printf ("Sun is circumpolar\n"); else { ln_get_local_date (rst.rise, &rise); ln_get_local_date (rst.transit, &transit); ln_get_local_date (rst.set, &set); print_date ("Rise", &rise); print_date ("Transit", &transit); print_date ("Set", &set); } return 0; }