I'm currently on R trying to create for a DF multiple columns with the sum of previous one. Imagine I got a DF like this:
df=
sep-2016 oct-2016 nov-2016 dec-2016 jan-2017
1 70 153 NA 28 19
2 57 68 73 118 16
3 29 NA 19 32 36
4 177 36 3 54 53
and I want to add at the end the sum of the rows previous of the month that I'm reporting so for October you end up with the sum of sep and oct, and for November you end up with the sum of sep, oct and november and end up with something like this:
df=
sep-2016 oct-2016 nov-2016 dec-2016 jan-2017 status-Oct2016 status-Nov 2016
1 70 153 NA 28 19 223 223
2 57 68 73 118 16 105 198
3 29 NA 19 32 36 29 48
4 177 36 3 54 53 213 93
I want to know a efficient way insted of writing a lots of lines of rowSums() and even if I can get the label on the iteration for each month would be amazing!
Thanks!
We can use lapply to loop through the columns to apply the rowSums.
dat2 <- as.data.frame(lapply(2:ncol(dat), function(i){
rowSums(dat[, 1:i], na.rm = TRUE)
}))
names(dat2) <- paste0("status-", names(dat[, -1]))
dat3 <- cbind(dat, dat2)
dat3
# sep-2016 oct-2016 nov-2016 dec-2016 jan-2017 status-oct-2016 status-nov-2016 status-dec-2016 status-jan-2017
# 1 70 153 NA 28 19 223 223 251 270
# 2 57 68 73 118 16 125 198 316 332
# 3 29 NA 19 32 36 29 48 80 116
# 4 177 36 3 54 53 213 216 270 323
DATA
dat <- read.table(text = " 'sep-2016' 'oct-2016' 'nov-2016' 'dec-2016' 'jan-2017'
1 70 153 NA 28 19
2 57 68 73 118 16
3 29 NA 19 32 36
4 177 36 3 54 53",
header = TRUE, stringsAsFactors = FALSE)
names(dat) <- c("sep-2016", "oct-2016", "nov-2016", "dec-2016", "jan-2017")