1

I have a data frame like the following:

a b c d e
1 2 3 1 1
2 3 0 1 1 
3 4 2 1 1
4 5 0 1 2
5 0 7 1 2

I would like to sum each column for each unique value in column e. So my output should be:

a b c d e
6 9 5 3 1
9 5 7 2 2

How can I do it?

Asmita Poddar
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    You want to summarise by group. You can do: `library(dplyr); data %>% (e) %>% summarise_all(sum)` – patL Jun 12 '19 at 07:45

1 Answers1

2

With by

cbind(do.call(rbind, by(d[-5], d$e, colSums)), e=unique(d$e))
#   a b c d e
# 1 6 9 5 3 1
# 2 9 5 7 2 2

or use aggregate

aggregate(. ~ e, d, FUN=sum)
#   e a b c d
# 1 1 6 9 5 3
# 2 2 9 5 7 2

Data

d <- structure(list(a = 1:5, b = c(2L, 3L, 4L, 5L, 0L), c = c(3L, 
0L, 2L, 0L, 7L), d = c(1L, 1L, 1L, 1L, 1L), e = c(1L, 1L, 1L, 
2L, 2L)), row.names = c(NA, -5L), class = "data.frame")
jay.sf
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