Aggregate() with more functions -
aggregate, r
Solution
Wrap it in `do.call(data.frame, ...)`:
aggdata <-aggregate(mtcars["cyl"], by=list(mtcars$cyl),
FUN=function(x) c(length(x),mean(x)))
do.call(data.frame, aggdata)
# Group.1 cyl.1 cyl.2
# 1 4 11 4
# 2 6 7 6
# 3 8 14 8
str(do.call(data.frame, aggdata))
# 'data.frame': 3 obs. of 3 variables:
# $ Group.1: num 4 6 8
# $ cyl.1 : num 11 7 14
# $ cyl.2 : num 4 6 8
After searching a little bit, I just found the source of my answer. There are a few other questions similar to this, but this was where I learned the `do.call(data.frame, ...)` approach.
(Came to mind what to search for after @James added the same answer as I did and deleted his....)
Problem
Can I use `aggregate()` with more functions in such way that aggregations are stored as separate columns and not as part of a matrix? I want to have data frame with columns `Group.1, cyl.1, cyl.2`, not `Group.1, cyl`. ``` # Only one function > aggdata <-aggregate(mtcars["cyl"], by=list(vs), FUN=mean, na.rm=TRUE) > aggdata Group.1 cyl 1 0 7.444444 2 1 4.571429 > str(aggdata) 'data.frame': 2 obs. of 2 variables: $ Group.1: num 0 1 $ cyl : num 7.44 4.57 > # Two functions > aggdata <-aggregate(mtcars["cyl"], by=list(cyl), FUN=function(x) c(length(x),mean(x))) > aggdata Group.1 cyl.1 cyl.2 1 4 11 4 2 6 7 6 3 8 14 8 > str(aggdata) 'data.frame': 3 obs. of 2 variables: $ Group.1: num 4 6 8 $ cyl : num [1:3, 1:2] 11 7 14 4 6 8 > aggdata$cyl [,1] [,2] [1,] 11 4 [2,] 7 6 [3,] 14 8 ```