[R] Inflection Points

From: Martin aus Chemnitz <MartinAusChemnitz_at_gmx.net>
Date: Fri 02 Jul 2004 - 01:49:57 EST


Hi!

Some weeks ago I discovered R. Now, I have a somewhat complicated task and am not sure whether R is the right tool to solve it.

I got data of several series or measurements where I have to find the two inflection points. I did a linear regression (with ^2 and ^3 arguments), the problem there was that I had to look only at a very narrow band of measurement in order to get the approximation right at the essential point. (Maybe there is a better way than lm?)

Now that I have an appromiated function, I need its inflection point, but I could not find any R function for that. Is there any? Or can anyone recommend a good (possibly free) mathematical programme?

Maybe this could be helpful: All the measurements look like this and I marked the points of interest.

                  ,-------
                 /
                /  <--
               /
         ,----
        /
       |  <--
       /

-----

Thank you very much for your help

Martin



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https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html Received on Fri Jul 02 01:53:15 2004

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