In R  Change For Loops into "apply", "tapply", "sapply" and etc
Thanks for reading this thread. I'm relatively new to R so this question might seem stupid.
So, I have a data set on product prices. It is a 240 by 1,000 matrix. Each column represents a unique product and each row gives price info of the 1,000 at a specific month. I'm trying to resample the data set and get a new matrix of the same dimensions.

My data is saved as "data"

I would want to save the bootstrapped results in "newdata", which is an empty 240x1,000 matrix
Here's my code:
for (month in 1:num.months) { for (n in 1:num.products) { newdata[month, n] < mean(sample(data[month, ], size = num.productss, replace = TRUE)); } }
This works but the For Loops make things really slow. It would be great if someone can point out how I could improve the speed by using apply, sapply, tapply, and etc. Thanks.