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rdataframeaggregatesummarize

Search and combine text from the same columns related to a specific variable in R

i have the following example data frame in R:

ID = c(rep(1,4),rep(2,3),rep(3,2),4,5);ID
VAR = c(rep("A",3),"B",rep("C",2),"D",rep("E",2),"F","G");VAR
D = data.frame(ID,VAR);D

My purpose is to construct a separate variable outside the data frame that will search all the ids and print the combined texts related to each id. For example the data frame

ID VAR
1 A
1 A
1 A
1 B
2 C
2 C
2 D
3 E
2 E
4 F
5 G

ideal output given the above data frame in R will be :

ID TEXTS
1 A,B
2 C,D
3 E
4 F
5 G

Any help ?

Solution

  • You can try this

    > aggregate(. ~ ID, unique(D), c)
  ID  VAR
1  1 A, B
2  2 C, D
3  3    E
4  4    F
5  5    G

    or

    > aggregate(. ~ ID, unique(D), toString)
  ID  VAR
1  1 A, B
2  2 C, D
3  3    E
4  4    F
5  5    G