I got a Data Frame:
a <- c('A','A','B','B','A')
b <- c(1,1,1,1,2)
c <- c(NA,60,NA,100,NA)
d <- c(10,NA,10,NA,100)
frame <- data.frame(a,b,c,d)
> frame
a b c d
1 A 1 NA 10
2 A 1 60 NA
3 B 1 NA 10
4 B 1 100 NA
5 A 2 NA 100
And I want to aggregate it by a and b
>frame2
a b c d
1 A 1 60 10
3 B 1 100 10
5 A 2 NA 100
I tried several things like aggregat() and group from dplyr but somehow it never works. I guess the NA is a problem.
With aggregate, we may need to use na.action
aggregate(.~ a + b, frame, sum, na.rm = TRUE, na.action = 'na.pass')
# a b c d
#1 A 1 60 10
#2 B 1 100 10
#3 A 2 0 100
If we intend to subset the rows
library(dplyr)
frame %>%
group_by(a, b) %>%
mutate_at(vars(-group_cols()), ~ .[order(is.na(.))]) %>%
slice(1)
# A tibble: 3 x 4
# Groups: a, b [3]
# a b c d
# <fct> <dbl> <dbl> <dbl>
#1 A 1 60 10
#2 A 2 NA 100
#3 B 1 100 10