Suppose I have the vector ["a","b","c"], then I'd like to create a list of vectors of all the unique combinations, of all sizes (order does not matter):
["a"]
["b"]
["c"]
["a","b"]
["a","c"]
["b","c"]
["a","b","c"]
How can I do this in R?
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CodeGuy
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It has not been answered. The linked question does not return a list of lists. – CodeGuy Oct 14 '16 at 18:06
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3Just remove the `do.call(c, ...)` wrapper, then it will be a list of lists. – Rich Scriven Oct 14 '16 at 18:08
1 Answers
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We can try with combn
do.call("c", lapply(seq_along(v1), function(i) combn(v1, i, FUN = list)))
data
v1 <- letters[1:3]
akrun
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2@CodeGuy What you have showed is a structure in another language. In R, vector structure is not as the one you showed. Also, in `R`, array can be either matrix (2 dimensional) or higher dimensions (with lengths equal). However, a `list` can accomodate vectors of different length. THat is the reason I place the vectors in a `list` – akrun Oct 14 '16 at 18:04
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1we found the Java progammer ;-), do you need it the way you outlined in your Question, if so just do this lapply(seq_along(v1), function(i) combn(v1, i, FUN = list)) – infominer Oct 14 '16 at 18:10
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