Combining data
On Nov 17, 2011, at 10:37 AM, Nasrin Pak wrote:
Hi all; It seemed to be easy at first, but I didn't manage to find the answer through the google search. I have a set of data for every second of the experiment, but I don't need such a high resolution for my analysis. I want to replace every 30 row of my data with their average value. And then save the new data set in a new csv file to be able to have a smaller excel data sheet. What is the command for combining certain number of data into their average value?
This aggregates mean values in groups of ten.
> aggregate(data.frame(a=rnorm(100)), list(rep(1:10, each=10)),
FUN=mean)
Group.1 a
1 1 -0.59492893
2 2 0.20087525
3 3 -0.06310919
4 4 -0.60778424
5 5 -0.01435818
6 6 -0.01159243
7 7 0.05921309
8 8 -0.04881492
9 9 0.43796040
10 10 -0.02968688
Thank you -- Nasrin Pak MSc Student in Environmental Physics University of Calgary [[alternative HTML version deleted]]
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