Permutation test in R for a bivariate Pearson correlation

The permutation test recommended by for testing if a correlation is zero can be used in R

Suppose we have two columns of data

a <- c(1,2,3)
b <- c(3,6,5)

then the two-sided p-value for testing of the a,b Pearson correlation equals zero is outputted using pout (assuming 1000 simulations).

robs <- cor(a,b)
repout <- replicate(1000,cor(a,sample(b)))
rout<-(abs(repout)>robs)
pout<-sum(rout=="TRUE")/1000