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rdata-cleaning

R: length of vector not equal to column numbers

I have vectors with varying length, like 3,7,9,19etc. I’d like to use these vectors to fill in multiple columns in each row. I have 19 columns in total.

When the vector length is smaller than 19, I’d like to fill those columns with NA. How should I do it in R? Thanks!

Solution

  • You can use `length<-`, for example

    # dummy data `x`
> (x <- lapply(c(3, 7, 9, 19), seq_len))
[[1]]
[1] 1 2 3

[[2]]
[1] 1 2 3 4 5 6 7

[[3]]
[1] 1 2 3 4 5 6 7 8 9

[[4]]
 [1]  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19


> Map(`length<-`, x, 19)
[[1]]
 [1]  1  2  3 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA

[[2]]
 [1]  1  2  3  4  5  6  7 NA NA NA NA NA NA NA NA NA NA NA NA

[[3]]
 [1]  1  2  3  4  5  6  7  8  9 NA NA NA NA NA NA NA NA NA NA

[[4]]
 [1]  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19