R: Pivot from long to vector-CodePudding

Is there a way to summarize occurrences of variable values by another variable?

It's similar to pivoting from long to wide, but pivoting is done into a vector rather than into multiple variables

data have:

| var1 | var2   |
| :--: |:------:|
| 1    | 2      |
| 1    | 4      |
| 1    | 4      |
| 1    | 4      |
| 1    | 6      |
| 2    | 8      |
| 2    | 8      |
| 2    | 10     |
| 2    | 12     |

data want:

| var1 | var2      |
| :--: |:---------:|
| 1    | (2, 4, 6) |
| 2    | (8,10,12) |

CodePudding user response：

We could create a list column after getting the unique elements

library(dplyr)
df1 %>%
  distinct %>%
  group_by(var1) %>%
  summarise(var2 = list(var2))

CodePudding user response：

A base R approach with aggregate

aggregate(. ~ var1, df, function(x) list(unique(x)))
  var1      var2
1    1   2, 4, 6
2    2 8, 10, 12