A vectorized alternative to rep(`each=`) in R-CodePudding

I get a warning message in rep() that says each= argument is not vectorized.

Is there a vectorized alternative to rep() perhaps in tidyverse() or other base R alternative?

n_study <- 5
n_per_study_rows <- c(3,5,3,3,2)
rep(1:n_study, each=n_per_study_rows)

Warning message: first element used of 'each' argument

CodePudding user response：

Use the times argument, not the each argument:

n_study <- 5
n_per_study_rows <- c(3,5,3,3,2)
rep(1:n_study, times=n_per_study_rows)
#>  [1] 1 1 1 2 2 2 2 2 3 3 3 4 4 4 5 5

^{Created on 2021-10-25 by the reprex package (v2.0.0)}

CodePudding user response：

It's not clear to me from the question whether you actually wanted the each or times version of rep. To use the each version, you can use rep inside sapply:

unlist(sapply(n_per_study_rows, function(x) rep(1:n_study, each = x)))
#>  [1] 1 1 1 2 2 2 3 3 3 4 4 4 1 1 1 1 1 2 2 2 2 2 3 3 3 3 3 4 4 4 4 4 1 1
#> [35] 1 2 2 2 3 3 3 4 4 4 1 1 1 2 2 2 3 3 3 4 4 4 1 1 2 2 3 3 4 4