R Generate random binary vector of fixed length with fixed sum

Question

Quick question: In R, how to generate a random binary vector of fixed length with fixed sum.

For example:

I want a binary vector of length 100 that sum up to 15.

Thanks!

John Coleman · Accepted Answer · 2021-06-29 20:32:57Z

1

You could write a function for this:

rand_binary <- function(n,k){
  v <- numeric(n)
  v[sample(seq_along(v),k)] <- 1
  v
}

And then rand_binary(100,15) evaluates to a randomly chosen vector consisting of 85 0s and 15 1s.

answered Jun 29, 2021 at 20:32

John Coleman

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Comments

ThomasIsCoding · Accepted Answer · 2021-06-29 21:33:03Z

0

We can do something like below

replace(rep(0, 100), sample(100, 15), 1)

answered Jun 29, 2021 at 21:33

ThomasIsCoding

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