Hello,
Far from the "absolute fastest" but apparently portable,
big <- function(con, n, pass=5000){
if(file.exists(con)) unlink(con)
fc <- file(con, "wb")
on.exit(close(fc))
m <- n %/% pass
r <- n %% pass
replicate(m, writeBin(double(pass), fc))
if(r) writeBin(double(r), fc)
invisible(n)
}
system.time(big("zeros", n=1e7 + 1L))
user system elapsed
0.07 0.06 0.14
Changing the default 'pass' doesn't make it faster. (On my system, Win7, R
14.2.)
Rui Barradas
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