R - aggregating sum row wise

Question

I have a data frame mydf as mydf <- data.frame(month = c('apr', 'may', 'june'),cost = c(100, 150, 200))

I wish to get a runningTotal that sums each record cumulatively

  month cost runningTotal
1   apr  100          100
2   may  150          250
3  june  200          450

I tried using dplyr sum but didn't work. Can someone help me find the most efficient way of doing this Thanks.

`mydf$runningTotal=cumsum(mydf$cost)` – cryo111 Sep 13 '16 at 12:34 — cryo111, Sep 13 '16 at 12:34

score 0 · Accepted Answer · answered Sep 13 '16 at 12:33

0

We can use cumsum

library(dplyr)
mydf%>%
   mutate(runningTotal = cumsum(cost))

answered Sep 13 '16 at 12:33

akrun

1 Answers1