FotS

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===Phase of the Moon for given date===

Shows the Phase of the moon as an integer from 0 to 7.

Inspired by the first algorithm on this [[http://www.voidware.com/moon_phase.htm|page]] (unable to find a credit - do you know different?) and first published on The Back Shed [[https://www.thebackshed.com/forum/forum_posts.asp?TID=10472&PN=1|here]].

Provide the day, month and year as separate integers.

**Syntax**:
=MoonPhase(dd,mm,yyyy)

**Examples**:
Print MoonPhase(1,1,2000)
z=MoonPhase(24,12,2019)

<code>
Function MoonPhase(d As Integer,m As Integer,y As Integer) As Integer
	'calculates the moon phase (0-7), accurate to 1 segment.
	'0 => new moon, 4 => full moon, 7= last part of third quarter (before new)
	Local Float j
	If m<3 Then y=y-1:m=m+12
	m=m+1
	j=(((365.25*y)+(30.6*m)+d)-694039.09)/29.53    'total days divided by the moon cycle
	MoonPhase=Fix((j-Int(j))*8) Mod 7
End Function
</code>