deathstar example

aws.estimatePi.R

library(AWS.tools)
library(rzmq)


estimatePi <- function(seed) {
    set.seed(seed)
    numDraws <- 1e6

    r <- .5
    x <- runif(numDraws, min=-r, max=r)
    y <- runif(numDraws, min=-r, max=r)
    inCircle <- ifelse( (x^2 + y^2)^.5 < r , 1, 0)
    
    sum(inCircle) / length(inCircle) * 4
}

cl <- startCluster(ami="ami-9d5f93f4",key="maher-ave",instance.count=2,instance.type="c1.xlarge")
print("starting sim.")
run.time <- system.time(ans <- zmq.cluster.lapply(cluster=cl$instances[,"dnsName"],as.list(1:1e3),estimatePi))
print("sim completed.")
res <- terminateCluster(cl)


print(mean(unlist(ans)))
print(run.time)
print(attr(ans,"execution.report"))

pi.est <- mean(unlist(ans))
print("result:")
print(pi.est)