test join of plyr, dplyr and data.table

library(nycflights13)
library(plyr)
library(dtplyr)
library(data.table)
library(dplyr)
library(pipeR)
library(microbenchmark)

flights_DT <- data.table(flights)
weather_DT <- data.table(weather)

joinVars <- c("year", "month", "day", "hour", "origin", "time_hour")
microbenchmark(# base = {merge.data.frame(flights, weather, by = joinVars)},
  dataTable = {merge(flights_DT, weather_DT, by = joinVars)},
               plyr = {plyr::join(flights_DT, weather_DT, by = joinVars)},
               dplyr = {dplyr::left_join(flights_DT, weather_DT, by = joinVars)},
               times = 30L)

# Unit: milliseconds
# expr        min         lq       mean     median         uq       max neval
# dataTable   69.82381   74.44107   83.44853   76.92261   83.58021  137.6093    30
# plyr      1247.76173 1343.87015 1375.15348 1367.48452 1402.75731 1568.7255    30
# dplyr      110.05879  119.43608  159.57693  165.37475  186.57999  223.1082    30