bench.r

sign1 <- function(x) {
  if (x > 0) {
    1
  } else if (x == 0) {
    0
  } else {
    -1
  }
}

cppFunction('
  int sign2(const int x) {
    if (x > 0) {
      return(1);
    } else if (x == 0) {
      return(0);
    } else {
      return(-1);
    }
  }'
)

library(microbenchmark)
microbenchmark(
  sign(1),
  sign1(-1), 
  sign2(-1L))

# Unit: nanoseconds
#       expr  min     lq median     uq   max neval
#    sign(1)  212  236.0  265.5  280.0  2175   100
#  sign1(-1) 1549 1615.5 1654.0 1698.5 17375   100
# sign2(-1L) 1135 1207.0 1243.0 1288.5 13647   100