[Solved] in R, How to sum by flowing row in a data frame
[ad_1] We could use shift from data.table library(data.table) m1 <- na.omit(do.call(cbind, shift(df1$col1, 0:4, type=”lead”))) rowSums(m1*(1:5)[col(m1)]/5) #[1] 13.60 12.20 31.24 25.58 30.48 32.58 44.88 Or another option m1 <- embed(df1$col1,5) rowSums(m1*(5:1)[col(m1)]/5) #[1] 13.60 12.20 31.24 25.58 30.48 32.58 44.88 [ad_2] solved in R, How to sum by flowing row in a data frame