#!/usr/bin/env python # # season_math_test.py - convert from month to season and vice versa # # Copyright (C) 2015 Antonio Ospite # # This program is free software. It comes without any warranty, to # the extent permitted by applicable law. You can redistribute it # and/or modify it under the terms of the Do What The Fuck You Want # To Public License, Version 2, as published by Sam Hocevar. See # http://sam.zoy.org/wtfpl/COPYING for more details. # The code assumes meteorological seasons. # See http://en.wikipedia.org/wiki/Season # # Default seasons order is the one for the Northern hemisphere. seasons_norhtern = ["Winter", "Spring", "Summer", "Fall"] seasons_southern = ["Summer", "Fall", "Winter", "Spring"] seasons = seasons_norhtern months = ["January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"] def season(month): if month < 0 or month > 11: raise ValueError("Invalid month %d" % month) # Rotate forward by one month because Winter starts in December, # and group by three months because each season is three months long. return ((month + 1) % 12) // 3 def first_month_of_season(season): if season < 0 or season > 3: raise ValueError("Invalid season %d" % season) # Expand by three because a new season starts every 3 months, # and rotate back by one month because December is the first # month of Winter return (season * 3 - 1) % 12 def test(function): try: eval(function) except Exception as e: print e.message if __name__ == "__main__": test("season(-1)") test("season(12)") test("first_month_of_season(-1)") test("first_month_of_season(4)") print for i, m in enumerate(months): j = season(i) print "Month: %s. (%d) \tSeason: %s (%d)" % (m[0:3], i, seasons[j], j) print for i, s in enumerate(seasons): j = first_month_of_season(i) print "Season: %s (%d)\tFirst month: %s (%d)" % (s, i, months[j], j)