I want to compute monthly summaries from daily data. I want to choose which month to start and how many months to total over. Default could be to start in January and total over 3 months. For the number of rain days the default threshold is 0.85mm.
I tried to make a function which sum all months not some of months. I will appreciate any help from you guys. Thanks. Here is the data and the code I used. > dput(head(kitale))structure(list(Year = c(1979L, 1979L, 1979L, 1979L, 1979L, > 1979L ), Month = c(1L, 1L, 1L, 1L, 1L, 1L), Day = 1:6, Rain = c(0, 0, 0, 0, 0, 0)), .Names = c("Year", "Month", "Day", "Rain"), row.names = c(NA, 6L), class = "data.frame") here is the function: total = function(data, threshold = 0.85){ month_tot=matrix(NA,31,12) rownames(month_tot)=as.character(1979:2009) colnames(month_tot)=c("Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec") raindays=month_tot # loop over months and years to get summary statistics for (mon in 1:12) { rain=data[data[2]==mon,c(1,4)] # rain just for a specific month for (yr in 1979:2009) { month_tot[yr-1978,mon]=sum(rain[rain[,1]==yr,2]) raindays[yr-1978,mon]=sum(rain[rain[,1]==yr,2]>threshold) } } month_tot } Regards, Frederic. Frederic Ntirenganya Maseno University, African Maths Initiative, Kenya. Mobile:(+254)718492836 Email: fr...@aims.ac.za https://sites.google.com/a/aims.ac.za/fredo/ [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.