Merge from X250

moonphase.py

@@ -0,0 +1,43 @@
+#!/usr/bin/env python
+"""
+moonphase.py - Calculate Lunar Phase
+Author: Sean B. Palmer, inamidst.com
+Cf. http://en.wikipedia.org/wiki/Lunar_phase#Lunar_phase_calculation
+"""
+
+import math, decimal, datetime
+dec = decimal.Decimal
+
+def position(now=None): 
+   if now is None: 
+      now = datetime.datetime.now()
+
+   diff = now - datetime.datetime(2001, 1, 1)
+   days = dec(diff.days) + (dec(diff.seconds) / dec(86400))
+   lunations = dec("0.20439731") + (days * dec("0.03386319269"))
+
+   return lunations % dec(1)
+
+def phase(pos): 
+   index = (pos * dec(8)) + dec("0.5")
+   index = math.floor(index)
+   return {
+      0: "New Moon", 
+      1: "Waxing Crescent", 
+      2: "First Quarter", 
+      3: "Waxing Gibbous", 
+      4: "Full Moon", 
+      5: "Waning Gibbous", 
+      6: "Last Quarter", 
+      7: "Waning Crescent"
+   }[int(index) & 7]
+
+def main(): 
+   pos = position()
+   phasename = phase(pos)
+
+   roundedpos = round(float(pos), 3)
+   print "%s (%s)" % (phasename, roundedpos)
+
+if __name__=="__main__": 
+   main()