r - Gather the values of one column based on another column of a dataframe and create list of named lists with them

Question

I have the dataframe below:

name<-c("Jack","Bob","Jack","Bob")
item<-c("apple","olive","banana","tomato")
d<-data.frame(name,item)


name   item
1 Jack  apple
2  Bob  olive
3 Jack banana
4  Bob tomato

and I would like to create a list which will include as many lists as the unique values of name and each one will include the values of item that correspond to that name. The new list will be like:

words
[[1]]
[1] "apple"  "banana"

[[2]]
[1] "olive"  "tomato"

if instead of [[1]] and [[2]] I could have the actual values of name that correspond, [[Jack]] and [[Bob]] it would be good as well.

Answer 1

Try this creating a list with split() and then formating the data as you wish:

#Code
L1 <- split(d,d$name)
L1 <- lapply(L1,function(x) {x$name<-NULL;x})
L1 <- lapply(L1,function(x) {y<- x$item;y})

Output:

L1
$Bob
[1] "olive"  "tomato"

$Jack
[1] "apple"  "banana"

For sure you can use L1['Bob'] and so on to explore the list.

The fast way can be (Many thanks and credits to @mt1022):

#Code2
L <- split(d$item, d$name)

Output:

L
$Bob
[1] "olive"  "tomato"

$Jack
[1] "apple"  "banana"