calendar_change

julian_day(time)

julian_day_fast(time)

julian_century(time)

geom_mean_lon_sun(x)

geom_mean_anom_sun(x)

eccent_earth_orbit(x)

sun_eq_of_ctr(x, anom)

sun_rad_vector(eccent, anom)

sun_app_lon(x, lon)

mean_obliq_eclip(x)

obliq_corr(x, eclip)

sun_rt_ascen(app.lon, obliq.corr)

sun_decline(app.lon, obliq.corr)

var_y(obliq.corr)

eq_of_time(mean.lon, eccent.earth, anom.mean, var.y)

ha_sunrise(lat, decline, nag = 0)

solar_noon(lon, eq.of.time)

sunrise(noon, ha.sunrise)

sunset(noon, ha.sunrise)

sunlight_duration(ha.sunrise, unit.out = "hours")

solar_datetime(time, lat, lon, eq.of.time)

solar_tod(time, lat, lon, eq.of.time)

hour_angle(solar.time)

zenith_angle(lat, hour.angle, decline)

elevation_angle(lat, hour.angle, decline)

atm_refraction_approx(elevation.angle)

azimuth_angle(lat, hour.angle, zenith.angle, decline)