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Filter values ​​from a list in R

I want to calculate the average of a list of named numbers. There are numeric(0) values ​​that I want to delete first. In addition, I would like to know which list items contain numeric(0) values.

Here is an example of what the values ​​might look like:

 >r["gg",] $`01_1_er` gg 0.5176445 $`02_1_er` gg 0.4990959 $`03_1_er` gg 0.5691489 $`22_1_er` numeric(0) $`23_1_er` numeric(0) $`25_1_er` gg 0.386304

And here is the result of str:

 > str(r["gg",]) List of 6 $ 01_1_er: Named num 0.518 ..- attr(*, "names")= chr "gg" $ 02_1_er: Named num 0.499 ..- attr(*, "names")= chr "gg" $ 03_1_er: Named num 0.569 ..- attr(*, "names")= chr "gg" $ 22_1_er: num(0) $ 23_1_er: num(0) $ 25_1_er: Named num 0.386 ..- attr(*, "names")= chr "gg"

Can anyone help?

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3 answers
 ## Example list l <- list(n1=numeric(0), n2="foo", n3=numeric(0), n4=1:5) ## Filter out elements with length 0 l[lapply(l, length) > 0] $n2 [1] "foo" $n4 [1] 1 2 3 4 5 ## Get names of elements with length 0 names(l)[lapply(l, length) == 0] [1] "n1" "n3"
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Unlisting pulls out only numeric entries in a single vector, which you can call medium, so try:

 mean(unlist(r["gg",]))
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Another solution

 mean(unlist(Filter(is.numeric, l)))
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