>In Excel LOGEST() is used to perform exponential regression on a set of data points. If worst came to worst I could automate Excel, but I'd rather avoid it:
>
>- its accuracy is doubtful (www.npl.co.uk/npl/publications/news/ise/countingonit_issue9.pdf)
>- Excel may not be available
>
>Has anyone implemented anything like this in VFP? Is there an external library/.DLL callable from VFP? I've started to look into BLAS and the Intel MKL but they look like vast overkill.
>
>TIA.

If you know how to do a linear regression in VFP (I don't), you might be able to do something similar to the following:

Take the natural logarithm of every data item,

Do the linear regression on the result,

Take the anti-logarithm (exp()) of the result or result set.

HTH, Hilmar.

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