Calculation For the Beginning of a Month in the Hijri Calendar

hilal.py

#!/usr/bin/env python
'''
A simple script to calculate the beginning of month
in the Hijri calendar. For educational purposes only.
'''

import ephem
from datetime import datetime, timedelta

# start and end time
now = datetime(2018, 1, 1, 5, 0, 0)
end = datetime(2022, 12, 1, 5, 0, 0)

# initialize moon and sun
moon = ephem.Moon()
sun = ephem.Sun()

# location of the observer
observer = ephem.Observer()
observer.lon = '106.816667'
observer.lat = '-6.2'
observer.elevation = 8

# loop every day from now until end
yesterdayaltitude = 0
while now <= end:
    observer.date = now

    # sunset time
    sunsettime = observer.next_setting(sun)
    observer.date = sunsettime

    moon.compute(observer)

    # the altitude of the moon during the sunset, in degrees
    altitude = float(moon.alt) / 0.01745329252

    # if the moon is below the sun yesterday,
    # but it is above the sun now, then it is a new month
    if altitude > 0 and yesterdayaltitude <= 0:
        print("%s-%s-%s: %s°" % (now.year, now.month, now.day, altitude))

    # advance a day
    yesterdayaltitude = altitude
    now += timedelta(days = 1)