Appending a list to a list of lists in R

Could it be this, what you want to have:

# Initial list:
myList <- list()

# Now the new experiments
for(i in 1:3){
  myList[[length(myList)+1]] <- list(sample(1:3))
}

myList

outlist <- list(resultsa)
outlist[2] <- list(resultsb)
outlist[3] <- list(resultsc)

append's help file says it is for vectors. But it can be used here. I thought I had tried that before but there were some strange anomalies in the OP's code that may have mislead me:

outlist <- list(resultsa)
outlist <- append(outlist,list(resultsb))
outlist <- append(outlist,list(resultsc))

Same results.

There are two other solutions which involve assigning to an index one past the end of the list. Here is a solution that does use append.

resultsa <- list(1,2,3,4,5)
resultsb <- list(6,7,8,9,10)
resultsc <- list(11,12,13,14,15)

outlist <- list(resultsa)
outlist <- append(outlist, list(resultsb))
outlist <- append(outlist, list(resultsc))

which gives your requested format

> str(outlist)
List of 3
 $ :List of 5
  ..$ : num 1
  ..$ : num 2
  ..$ : num 3
  ..$ : num 4
  ..$ : num 5
 $ :List of 5
  ..$ : num 6
  ..$ : num 7
  ..$ : num 8
  ..$ : num 9
  ..$ : num 10
 $ :List of 5
  ..$ : num 11
  ..$ : num 12
  ..$ : num 13
  ..$ : num 14
  ..$ : num 15

This answer is similar to the accepted one, but a bit less convoluted.

L<-list()
for (i in 1:3) {
L<-c(L, list(list(sample(1:3))))
}

By putting an assignment of list on a variable first

myVar <- list()

it opens the possibility of hiearchial assignments by

myVar[[1]] <- list()
myVar[[2]] <- list()

and so on... so now it's possible to do

myVar[[1]][[1]] <- c(...)
myVar[[1]][[2]] <- c(...)

or

myVar[[1]][['subVar']] <- c(...)

and so on

it is also possible to assign directly names (instead of $)

myVar[['nameofsubvar]] <- list()

and then

myVar[['nameofsubvar]][['nameofsubsubvar']] <- c('...')

important to remember is to always use double brackets to make the system work

then to get information is simple

myVar$nameofsubvar$nameofsubsubvar

and so on...

example:

a <-list()
a[['test']] <-list()
a[['test']][['subtest']] <- c(1,2,3)
a
$test
$test$subtest
[1] 1 2 3


a[['test']][['sub2test']] <- c(3,4,5)
a
$test
$test$subtest
[1] 1 2 3

$test$sub2test
[1] 3 4 5

a nice feature of the R language in it's hiearchial definition...

I used it for a complex implementation (with more than two levels) and it works!

Appending a list to a list of lists in R

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