Generating repeatable sequences of random numbers

Problem

You want to generate a sequence of random numbers, and then generate that same sequence again later.

Solution

Use set.seed(), and pass in a number as the seed.

set.seed(423)
runif(3)
# 0.1089715 0.5973455 0.9726307

set.seed(423)
runif(3)
# 0.1089715 0.5973455 0.9726307