0
name

[[1]]

[1] "John"  "Davis"

[[2]]

[1] "Angela"   "Williams"

[[3]]

[1] "Bullwinkle" "Moose"

The data is as above, I want to take last and first name from the list. The code is: 

lastname <- sapply(name, "[", 2)

My question: what does the [ mean?

Sotos
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Tina
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1 Answers1

1

It is ?Extraction operator. Here, it extracts the 2nd element of the list. 

sapply(name, `[`, 2)

In the OP's post, the list elements are vectors. So, it checks the 2nd element and extract that element and output as a vector (sapply)

akrun
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