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Default excel's curve-smoothing algorithm

I have some raw data in excel, with a smooth curve added. I am trying
to reproduce this curve on the same data in GraphPad Prism, with poor
results. Does anyone know how excel calculates curve smoothing?

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Default excel's curve-smoothing algorithm

As far as I can recall Microsoft uses a cubic spline but I have not seen the
exact formula.
Try Google with search term: excel spline
best wishes
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ps.com...
I have some raw data in excel, with a smooth curve added. I am trying
to reproduce this curve on the same data in GraphPad Prism, with poor
results. Does anyone know how excel calculates curve smoothing?



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Default excel's curve-smoothing algorithm

Brian Murphy has determined that the smoothing algorithm is a Bezier curve.
Find the link to this workbook (Smooth_curve_bezier_example_file.xls) in the
bottom part of this page:

http://www.xlrotor.com/resources/files.shtml

- Jon
-------
Jon Peltier, Microsoft Excel MVP
Tutorials and Custom Solutions
Peltier Technical Services, Inc. - http://PeltierTech.com
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wrote in message
ps.com...
I have some raw data in excel, with a smooth curve added. I am trying
to reproduce this curve on the same data in GraphPad Prism, with poor
results. Does anyone know how excel calculates curve smoothing?



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