Jamie Ledingham
2008-Jan-24 11:48 UTC
[R] Sliding Window Time Series Analysis - hourly rainfall
I have a time series of rainfall in a dataframe. I would like to be able to aggregate this using a sliding window approach- i.e. a new 24 hourly total is calculated for each hours rainfall. I'm struggling to understand how this might be achieved - currently I've tried looping a sum function to re-calculate a new total at every stage of the loop. for (inp[[9]] in 1:length(inp[[9]])){data.frame(x<-sum(inp[y:y+24,9]))} where inp is the data frame object and [[9]] is the column containing rainfall. y is used to try and get the previous 24 hours total however in it's current state it seems useless. If anyone could give me some pointers i'd be very pleased, I'm a bit new to the R language so any help appreciated. Thanks Jamie Ledingham
jim holtman
2008-Jan-25 01:13 UTC
[R] Sliding Window Time Series Analysis - hourly rainfall
Take a look at "filter" for doing a moving average. On Jan 24, 2008 6:48 AM, Jamie Ledingham <jamie.ledingham at newcastle.ac.uk> wrote:> I have a time series of rainfall in a dataframe. I would like to be > able to aggregate this using a sliding window approach- i.e. a new 24 > hourly total is calculated for each hours rainfall. I'm struggling to > understand how this might be achieved - currently I've tried looping a > sum function to re-calculate a new total at every stage of the loop. > > for (inp[[9]] in 1:length(inp[[9]])){data.frame(x<-sum(inp[y:y+24,9]))} > > where inp is the data frame object and [[9]] is the column containing > rainfall. > y is used to try and get the previous 24 hours total however in it's > current state it seems useless. > > If anyone could give me some pointers i'd be very pleased, I'm a bit new > to the R language so any help appreciated. > Thanks > Jamie Ledingham > > ______________________________________________ > R-help at 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 > and provide commented, minimal, self-contained, reproducible code. >-- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem you are trying to solve?