How do I have VBA return the trendline types possible for given d.

[Guest]

I have an Excel VBA program which applies each trendline type to data then
chooses the option with the best R^2 value. How can I have the program skip
unavailable options? For instance when I make the data very strange Power and
Exponential regressions are not available. This causes my macro to crash.

 

[Tom Ogilvy]

Trap the error - provide an error handler?

 

[Dana DeLouis]

Options are grayed out when you have negative numbers... depending on the
type of regression you are doing.

 

[Tushar Mehta]

Tom has already given you how to deal with your problem. At the same
time, using R-squared is not necessarily the best way to approach the
problem. A polynomial of power 6 will have a R-squared greater than a
polynomial of power 2 (or a linear fit). However, that doesn't
automatically make it a better fit. A linear or 2nd order polynomial
may be more appropriate for describing the data.

--
Regards,

Tushar Mehta
www.tushar-mehta.com
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