| sample {base} | R Documentation |
sample takes a sample of the specified size from
the elements of x using either with or without replacement.
sample(x, size, replace=FALSE, prob)
x |
Either a (numeric, complex, character or logical) vector of more than one elements from which to choose, or a positive integer. |
size |
A positive integer giving the number of items to choose. |
replace |
Should sampling be with replacement? |
prob |
A vector of probabilities of obtaining the elements of the vector being sampled. |
If x has length 1, sampling takes place from
1:x.
By default size is equal to length(x)
so that sample(x) generates a random permutation
of the elements of x (or 1:x).
The optional prob argument can be used to give a vector
of probabilities of obtaining the elements of the vector being
sampled. If replace is false, these probabilities are applied
sequentially, that is the probability of choosing the next item is
proportional to the probabilities amongst the remaining items.
x <- 1:12 # a random permutation sample(x) # bootstrap sampling sample(x,replace=TRUE) # 100 Bernoulli trials sample(c(0,1), 100, replace = TRUE)