[R] for loop optimization help
Jinsong Zhao
jszhao at yeah.net
Mon Aug 27 02:06:34 CEST 2012
Hi there,
In my code, there is a for loop like the following:
pmatrix <- matrix(NA, nrow = 99, ncol = 10000)
qmatrix <- matrix(NA, nrow = 99, ncol = 3)
paf <- seq(0.01, 0.99, 0.01)
for (i in 1:10000) {
p.r.1 <- rnorm(1000, 1, 0.5)
p.r.2 <- rnorm(1000, 2, 1.5)
p.r.3 <- rnorm(1000, 3, 1)
pmatrix[,i] <- quantile(c(p.r.1, p.r.2, p.r.3), paf)
}
for (i in 1:99) {
qmatrix[i,] <- quantile(pmatrix[i,], c(0.05, 0.5, 0.95))
}
Because of the number of loop is very large, e.g., 10000 here, the code
is very slow.
Is it possible to optimize the code?
Any suggestion will be greatly appreciated.
Regards,
Jinsong
More information about the R-help
mailing list