period of sum of sine waves

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From: LB (brunsonl_at_hotmail.com)
Date: 08/12/04 

Date: Thu, 12 Aug 2004 13:14:32 -0400

I'm trying to create a function to calculate the period of a sum of
sinusoids. This is nothing more than the least common multiple of the
periods of all contributions. I note that work*** function LCM does
not appear to be available in VBA. But that wouldn't work anyway since
it can't handle real arguments, so I create my own called LCM_real.
Problem with LCM_real is that it only accepts 2 arguments, but that can
be solved through using it in a looping function. I would like this
function to operate like the work*** one, in that you can place in the
argument up to 29 sine wave periods separated by commas, or you can
enter a range (no commas). I have the following code for comma
delimited argument:

Function PeriodOfSinuSum(ParamArray T() As Variant) As Double
Dim i As Integer, tmp As Double
tmp = LCM_Real(T(0), T(1))
For i = 2 To UBound(T())
    tmp = LCM_Real(tmp, T(i))
Next i
PeriodOfSinuSum = tmp
End Function

I note that this function doesn't work if you try entering a range, so I
come up with another one for that purpose:

Function PeriodOfSinuSumRange(T As Range) As Double
Dim i As Integer, tmp As Double
tmp = LCM_Real(T(1), T(2))
For i = 3 To UBound(T())
    tmp = LCM_Real(tmp, T(i))
Next i
PeriodOfSinuSumRange = tmp
End Function

This one works with a range, but doesn't work if you input each period
separated by a comma. Can anyone recommend a single function that will
accept both types of input?

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