Extracting unique numbers from string in R

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For the second answer, you can use gsub to remove everything from the string that’s not a number, then split the string as follows:

unique(as.numeric(unlist(strsplit(gsub("[^0-9]", "", unlist(ll)), ""))))
# [1] 7 6 1 5 2

For the first answer, similarly using strsplit, 

unique(na.omit(as.numeric(unlist(strsplit(unlist(ll), "[^0-9]+")))))
# [1]   7 667  11   5   2

PS: don’t name your variable list (as there’s an inbuilt function list). I’ve named your data as ll.

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