Call the element in a list

Question

>str(testdata[1])

 List of 1
 $ :'data.frame':   10640 obs. of  13 variables:
   ..$ logprice      : num [1:10640] 12.3 12.1 13.1 14 12.5 ...
   ..$ bedrooms      : int [1:10640] 3 2 3 4 3 3 3 4 3 4 ...

I skipped the rest of 11 variables. My question is, how to call out the "logprice" in this data set, testdata[1]$logprice doesn't work

Oh my god, your right. That's a stupid mistake. Thank you! – Kyle Mar 28 '18 at 22:11 — Kyle, Mar 28 '18 at 22:11

score 0 · Answer 1 · answered Mar 28 '18 at 22:20

In general, when working with lists [[]] returns a single element, whereas [] returns a list of elements. So when you try testdata[1] you're actually still returning a list (of one element) so you can't access what you want using $.

Mike H provided this solution as a comment, and Calum You was right in linking to this explanation if you want to understand the nuances a bit more.

Between all that hopefully the mistake isn't just obvious, but the explanation for it is too!

testdata[[1]]$logprice

Call the element in a list

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