Sigma Notation using VBA

[TakiMan]

Hi,

Similar to this thread: http://www.excelforum.com/excel-gene...-in-excel.html

I'm trying to come up with a VBA solution to.... Sigma from j=0 to i of: L((i-j)/i)*b*t. Any help would be appreciated, thanks.

[MrShorty]

In most programming languages, I would use some kind of For...Next loop for this: http://msdn.microsoft.com/en-us/library/5z06z1kb.aspx

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[TakiMan]

I did the following...

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Then I went back to the spreadsheet and input =Sigma(C7) and returned with error: "Compile error: Invalid outside procedure"

[MrShorty]

So you are trying to create a user-defined function (UDF). Here's a tutorial from MS on creating UDF's http://office.microsoft.com/en-us/ex...001111701.aspx

[zbor]

try this:

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Where you use formula as (based on this example):

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Where C6:C9 is range of your variables C6, C8 i C9 (C7 must be empty!!!). Or define them somewhere else.
And A1 is your value of i

[TakiMan]

Ok so here is what I did...

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... and then in an Excel cell I had: =Sigma(C7) and I get #VALUE! as the cell value. Cell C7 has the number '4' in it. Cells C6, C8, and C9 are all integers greater than '0'.

Where did I drop the ball?

[TakiMan]

try this:

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Where you use formula as (based on this example):

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Where C6:C9 is range of your variables C6, C8 i C9 (C7 must be empty!!!). Or define them somewhere else.
And A1 is your value of i

I just saw your post... I will try right away. THANKS!

[TakiMan]

It worked. Thanks zbor!