Hi
 Thanks for replying. I meant x[4] is the start of a peak shape and x[14] is
the end of that peak and x[9] is the maxima of the peak.
Thanks,
John




On Mon, Mar 24, 2008 at 11:09 PM, <Bill.Venables@csiro.au> wrote:

> It's hard to see how positions 4 and 14 correspond to 'peaks', they look
> like troughs to me.  So perhaps this is what you mean:
>
> > x <- c(14,15,12,11,12,13,14,15,16,15,14,13,12,11,14,12)
>
> > y <- which(x == min(x))
> > y
> [1]  4 14
>
> as a function:
>
> somefunction <- function(x) which(x == min(x))
>
>
> Bill Venables
> CSIRO Laboratories
> PO Box 120, Cleveland, 4163
> AUSTRALIA
> Office Phone (email preferred): +61 7 3826 7251
> Fax (if absolutely necessary):  +61 7 3826 7304
> Mobile:                         +61 4 8819 4402
> Home Phone:                     +61 7 3286 7700
> mailto:Bill.Venables@csiro.au
> http://www.cmis.csiro.au/bill.venables/
>
> -----Original Message-----
> From: r-help-bounces@r-project.org [mailto:r-help-bounces@r-project.org]
> On Behalf Of Research Scholar
> Sent: Tuesday, 25 March 2008 12:54 PM
> To: r-help@r-project.org
> Subject: [R] peak finding
>
> Hi all
>  Is there a function that can find the start and end position of peaks
> in a
> set of numbers.
> eg.
> x <- c(14,15,12,11,12,13,14,15,16,15,14,13,12,11,14,12)
> y <- somefunction(x)
>
> y
> 4 14
>
>
> Thanks
> John
>
>        [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help@r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html<http://www.r-project.org/posting-guide.html>
> and provide commented, minimal, self-contained, reproducible code.
>
>
>

	[[alternative HTML version deleted]]

