Category Archives: UDFs

Fitting high order polynomials

This post is a follow up to Using LINEST for non-linear curve fitting and the following comments from Scott Rogers and Lori Miller.  Scott found that he was getting different results from Linest and the xy chart trend line for polynomials of … Continue reading

Posted in AlgLib, Charts, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , , , , | 31 Comments

Finding all range names in a specified range

Another useful little snippet from Eng-tips. There was a question regarding how to list all the range names applied to a specified cell.  Forum members electricpete and MintJulep came up with a short macro to do the job, which I have … Continue reading

Posted in Excel, UDFs, VBA | Tagged , , , | 2 Comments

Evaluating higher order polynomials …

… and a better solution for quadratics. Having written a better solver for high order polynomials, that raises a few other issues.  The error in the roots found by the RPolyJT was checked by simply substituting each root as the … Continue reading

Posted in Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , , | 4 Comments

Solving higher order polynomials

The Quartic spreadsheet presented here previously (most recently here) uses algebraic techniques to provide an “exact” solution to polynomial equations of up to fouth order.  For polynomials of higher order there is no general algebraic solution, and numerical methods are … Continue reading

Posted in Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , , | 12 Comments

LatPile update

I have just posted an update to the LatpilePY spreadsheet, fixing a bug in the way in which it read the first row of data from input PY curves, which was resulting in the program failing to run if there were … Continue reading

Posted in Concrete, Excel, Geotechnical Engineering, Newton, UDFs, VBA | Tagged , , , , , , | 2 Comments