And another approach just for the heck of it. library(plyr)
# where dat1 is your data dd1 <- subset(dat1, Rain >= .01) dd1$Year <- as.factor(dd1$Year) dd1$Month <- as.factor(dd1$Month) count (dd1, .(Year, Month)) John Kane Kingston ON Canada > -----Original Message----- > From: hafizuddinarsha...@gmail.com > Sent: Tue, 19 May 2015 03:10:32 -0700 > To: r-help@r-project.org > Subject: [R] Count number in r > > Dear R users, > > Could someone help me on this? I have this kind of data set: > > structure(list(Year = c(1971L, 1971L, 1971L, 1971L, 1971L, 1971L, > 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, > 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, > 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, > 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, 1971L, > 1971L, 1971L), Month = c(1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, > 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, > 1L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, > 2L, 2L, 2L), Rain = c(58.9, 74.6, 17.7, 7.8, 1.2, 1, 5.3, 0.7, > 1.2, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, > 0, 10.4, 17.5, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0)), .Names = > c("Year", > "Month", "Rain"), class = "data.frame", row.names = c(NA, -44L > )) > > I want to count data in "Rain" that is greater and equal to 0.1 mm > according to their "Month" and "Year". I have used this code, but it > seems > so wrong. > > raindat <- read.csv('my data set',header=TRUE) > yearcorr<-min(raindat$Year)-1 > years<-unique(raindat$Year) > rainmonth<-as.data.frame(matrix(0,nrow=2,ncol=12)) > for(year in years) { > for(month in 1:12) { > if(any(raindat$Year==year&raindat$Month==month)) > rainmonth[year-yearcorr,month]<- > length((which(raindat$Rain >= > 0.1))[raindat$Year==year&raindat$Month==month]) > } > } > rownames(rainmonth)<-years > names(rainmonth)<-month.abb > rainmonth > > Thank you so much. > > > Arshad > > [[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. ____________________________________________________________ Can't remember your password? Do you need a strong and secure password? Use Password manager! It stores your passwords & protects your account. ______________________________________________ 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.