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Jerry W. Lewis Jerry W. Lewis is offline
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Default How can I get the average of curves on a plot?

If your data is noisy, then fitting a polynomial (as others suggested) can
smooth it before you average. However, if the data is not noisy and not from
a low order polynomial, you should be aware that a least squares fit need not
pass through any observed points.

If you really want to average what the chart displays, then the chart
smoother appears to fit Bezier curves

http://www.xlrotor.com/Smooth_curve_...ample_file.zip

which in most instances is not greatly different than cubic splines

http://groups.google.com/group/micro...2966520eccdb1f

(local polynomial fits that do pass through the data points, as opposed to a
global polynomial fit that may not).

Jerry

"jessie joe" wrote:


Hello!

I would like to get the average curve from several curves on a plot. Is
there a way to do this in Excel?

(Background infromation: I have, say, 10 sets of XY points and I want
to take the average of these to obtain a set of average X and Y points
and plot them. However, each of these 10 sets have a different amount
of XY points and I can't simply take the average across the row. Any
solutions?)

Thanks!


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jessie joe
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