import subprocess
r_prog = "printstats <- function(x) {\n    print( mean(x) )\n    print( sd(x))}"
r_prog += "\n" + "nums <- c(1, 2, 3, 4, 5)\nprintstats(nums)"
with open('prog.r', 'w') as fout:
    fout.write(r_prog)

cmd = "R --slave --vanilla"
subprocess.call(cmd.split(), stdin=open('prog.r'), universal_newlines=True)