[R] Challenge extracting months

[Jim Lemon]

Hi Kwesi,
Even without the data, it seems clear that you want something like a
rolling mean. Here is a simple function that will apply a function
like "mean" to successive bits of a vector of numbers:

collapse_values<-function(x,span,FUN="mean",na.rm=FALSE) {
 jump<-span-1
 newx<-rep(NA,length(x)-jump)
 for(i in 1:length(newx))
  newx[i]<-do.call(FUN,list(x[i:(i+jump)],na.rm=na.rm))
 return(newx)
}

test<-1:12
names(test)<-month.abb
test
collapse_values(test,3)
 [1]  2  3  4  5  6  7  8  9 10 11

Jim



On Mon, Jan 30, 2017 at 11:53 PM, Kwesi Quagraine
<starskykwesi at gmail.com> wrote:
> Hello, I have a data with two variables nodes and index, I want to extract
> 3 months seasons, with a shift of 1 month, that is, DJF, JFM, FMA etc to
> OND. Was wondering how to go about it. Kindly find attached the data as csv.
> Any help will be appreciated.
>
> Regards,
> Kwesi
>
> --
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