Select random element in a list of R?

Question

a<-c(1,2,0,7,5)

Some languages have a picker -function -- choose one random number from a -- how in R?

Answer 1

An alternative is to select an item from the vector using runif. i.e

a <- c(1,2,0,7,5)
a[runif(1,1,6)]

Lets say you want a function that picks one each time it is run (useful in a simulation for example). So

a <- c(1,2,0,7,5)
sample_fun_a <- function() sample(a, 1)
runif_fun_a <- function() a[runif(1,1,6)]
microbenchmark::microbenchmark(sample_fun_a(), 
                           runif_fun_a(),
                           times = 100000L)

Unit: nanoseconds

sample_fun_a() - 4665

runif_fun_a() - 1400

runif seems to be quicker in this example.