Displaying 1 result from an estimated 1 matches for "tp2308332p2308411".
2010 Jul 30
2
Summing by index
# build a sample data frame illustrating the problem
ids<-c(rep(1234,5),rep(5436,3),rep(7864,4))
years<-c(seq(1990,1994,by=1),seq(1991,1993,by=1),seq(1990,1993,by=1))
data<-seq(14,25,by=1)
data[6]<-NA
DF<-data.frame(Id=ids,Year=years,Data=data)
DF
Id Year Data
1 1234 1990 14
2 1234 1991 15
3 1234 1992 16
4 1234 1993 17
5 1234 1994 18
6 5436 1991 NA
7