[R] Sine function fitting

[Greg Snow]

If you know the period of the sine that you want to fit (just fitting the amplitude, phase shift, and offset) and are willing to assume normal errors (or at least normal enough for the CLT) then you can just use the lm function.  If you need to find the period as well (but still willing to assume normal enough errors) then you can use the nls function.  You can approximate with splines and lm for another approach. 

No packages (other than the automatic ones) needed.

If you are not willing to assume normal enough errors, then we will need more data to be able to help.

-- 
Gregory (Greg) L. Snow Ph.D.
Statistical Data Center
Intermountain Healthcare
greg.snow at imail.org
801.408.8111


> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
> project.org] On Behalf Of ashz
> Sent: Monday, October 18, 2010 6:46 AM
> To: r-help at r-project.org
> Subject: [R] Sine function fitting
> 
> 
> Hi,
> 
> Is there a package to perform a sine function fitting to XY data?
> 
> Thx,
> Ashz
> 
> --
> View this message in context: http://r.789695.n4.nabble.com/Sine-
> function-fitting-tp3000156p3000156.html
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