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removed sun.c as it has been moved to a new project

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see https://github.com/stv0g/sun
This commit is contained in:
Steffen Vogel 2013-01-19 19:37:31 +01:00
parent 1fe309c53c
commit f5c1da50aa
1 changed files with 0 additions and 83 deletions
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src/sun.c
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@ -1,83 +0,0 @@
#include "stdio.h"
#include "stdlib.h"
#include "string.h"
#include "math.h"
#include "time.h"
double deg2rad(double deg) {
return M_PI * deg / 180.0;
}
enum sun { RISE, SET };
enum out { HUMAN, UNIX };
double sun(enum sun mode, double lat, double lon, int timezone) {
const double h = -0.0145;
const double g = 0.2618;
time_t t = time(NULL);
struct tm *now = localtime(&t);
int days = now->tm_yday;
/* Zeitgleichung */
double zgl = -0.171 * sin(0.0337 * days + 0.465) - 0.1299 * sin(0.01787 * days - 0.168) ;
/* Deklination der Sonne */
double dekl = 0.4095 * sin(0.016906 * (days - 80.086));
/* Zeitdifferenz */
double zd = 12 * acos((sin(h) - sin(lat) * sin(dekl)) / (cos(lat) * cos(dekl))) / M_PI;
switch (mode) {
case SET: return 12 + zd - zgl + lon/g + timezone;
case RISE: return 12 - zd - zgl + lon/g + timezone;
default: return 0;
}
}
int main(int argc, char *argv[]) {
enum sun mode;
enum out output;
if (argc < 4 || argc > 6) goto usage;
if (strcmp(argv[1], "rise") == 0) mode = RISE;
else if (strcmp(argv[1], "set") == 0) mode = SET;
else goto usage;
if (argc >= 6) {
if (strcmp(argv[5], "human") == 0) output = HUMAN;
else if (strcmp(argv[5], "unix") == 0) output = UNIX;
else goto usage;
}
else {
output = HUMAN;
}
int timezone = (argc >= 5) ? atoi(argv[4]) : 0;
double lat = deg2rad(strtod(argv[2], NULL));
double lon = deg2rad(strtod(argv[3], NULL));
double time = sun(mode, lat, lon, timezone);
double intpart;
switch (output) {
case HUMAN:
printf("%d:%02d\n", (int) floor(time), (int) (modf(time, &intpart)*60));
break;
case UNIX:
printf("%d\n", (int) round(time*60*60));
break;
}
return 0;
usage:
fprintf(stderr, "usage: sun MODE LAT LON [TIMEZONE] [OUTPUT]\n");
fprintf(stderr, " MODE\t\t'rise' or 'set'\n");
fprintf(stderr, " LAT, LON\tthe geografical postition in degree\n");
fprintf(stderr, " TIMEZONE\tan integer describing the timezone offset\n");
fprintf(stderr, " OUTPUT\t'human' (default) or 'unix'\n");
return -1;
}