Add a mean column to a table dataframe in R - r

Question

I have a dataframe such as:
COL1 VALUE1 VALUE2
1 A,A 1 5
2 A,A,B 1 3
3 C 1 1
4 D 1 2
5 D 1 2
6 A,A 1 10
7 A,B,A 1 2
and I can succeed to remove duplicate within the COL1 and count the number of different duplicated in COL1 by using:
as.data.frame(table(tab$COL1)) %>%
group_by(Var1 = sapply(strsplit(as.character(Var1), ","), function(x) toString(unique(x)))) %>%
summarise(Freq = sum(Freq))
And then I get:
# A tibble: 4 × 2
Var1 Freq
<chr> <int>
1 A 2
2 A, B 2
3 C 1
4 D 2
But I wondered if someone had an idea in order to add a new column called Mean which would be for each COL1 groups, the mean of the VALUE2 values and then get:
Var1 Freq Mean
1 A 2 7.5 < because (5+10)/2 =7.5
2 A, B 2 2.5 < because (3+2)/2 =2.5
3 C 1 1 < because 1/1 = 1
4 D 2 2 < because (2+2)/2 = 2
Here is the dataframe if it can helps:
structure(list(COL1 = structure(c(1L, 2L, 4L, 5L, 5L, 1L, 3L), .Label = c("A,A",
"A,A,B", "A,B,A", "C", "D"), class = "factor"), VALUE1 = c(1L,
1L, 1L, 1L, 1L, 1L, 1L), VALUE2 = c(5L, 3L, 1L, 2L, 2L, 10L,
2L)), class = "data.frame", row.names = c(NA, -7L))

Answer 1

You can calculate the frequency table directly in the dplyr chain, and then just add a Mean = mean(VALUE2) in the summarise() call.
I.e.
tab %>%
group_by(Var1 = sapply(strsplit(as.character(COL1), ","), function(x) toString(unique(x)))) %>%
summarise(Freq = sum(VALUE1), Mean = mean(VALUE2))
# # A tibble: 4 x 3
# Var1 Freq Mean
# <chr> <int> <dbl>
# 1 A 2 7.5
# 2 A, B 2 2.5
# 3 C 1 1
# 4 D 2 2

Answer 2

Is this what you want:
library(dplyr)
tab %>%
mutate(COL1 = sapply(strsplit(as.character(COL1), ","), function(x) toString(unique(x)))) %>%
group_by(COL1) %>%
summarise(Freq = sum(VALUE1),
Mean = mean(VALUE2))
# A tibble: 4 x 3
COL1 Freq Mean
* <chr> <int> <dbl>
1 A 2 7.5
2 A, B 2 2.5
3 C 1 1
4 D 2 2