在R中使用for循环的Replicate（）

Question

I'd like to create a large number of samples in R and store them in a variable. I did some research and probably the best way is to use replicate()

record <- replicate(5000, sample(c(0,1), size = 60, replace = T,prob=c(0.9,0.1)))

My question is how would I do it using for loop? I can create 5000 samples using for loop but how do I store them?

x <- 'something here' #I want to store them in x

for (i in 1:5000)
    {record <- sample(c(0,1), size = 60, replace = T,prob=c(0.9,0.1))
    'x += record'}

Edit: The line X+= record is confusing. Here is my best shot at explaining that, in python I'd create a list and inside that list there'd be 5000 other lists each containing a different sample

Answer 1

I see no point in using a for loop; nor is there a need for replicate .

You can draw 5000 * 60 independent samples directly using

smpl <- sample(c(0, 1), size = 60 * 5000, replace = TRUE, prob = c(0.9, 0.1))

If you want to store smpl in a matrix, you can recast the vector as a matrix , eg

mat <- matrix(smpl, ncol = 5000)

This will give you a 60 x 5000 matrix, where every column contains 5000 random samples drawn from a distribution with p(0) = 0.9 and p(1) = 0.1 .

This will be faster than using a for loop or replicate .

Answer 2

What about

x <- list() # or x <- c() or x <- data.frame()

for (i in 1:5000){
    record <- sample(c(0,1), size = 60, replace = T,prob=c(0.9,0.1))
    x[[i]] <- record # or x <- c(x, record) or x <- rbind(x, record)
}

But yeah, not using a loop is probably better here, as indicated above.