Code for GGD blog post on microbenchmark

microbenchmark-blog-post.R

# see blog post here:
# http://gettinggeneticsdone.blogspot.com/2015/01/microbenchmark-package-r-compare-runtime-r-expressions.html

library(dplyr)
library(nycflights13)
flights

# base
aggregate(flights$arr_delay, by=list(flights$carrier), mean, na.rm=TRUE)

library(sqldf)
sqldf("SELECT carrier, avg(arr_delay) FROM flights GROUP BY carrier")

library(data.table)
flightsDT = data.table(flights)
flightsDT[ , mean(arr_delay, na.rm=TRUE), carrier]

library(dplyr)
flights %>% group_by(carrier) %>% summarize(mean(arr_delay, na.rm=TRUE))

library(microbenchmark)
mbm = microbenchmark(
  base = aggregate(flights$arr_delay, by=list(flights$carrier), mean, na.rm=TRUE),
  sqldf = sqldf("SELECT carrier, avg(arr_delay) FROM flights GROUP BY carrier"),
  datatable = flightsDT[ , mean(arr_delay, na.rm=TRUE), carrier],
  dplyr = flights %>% group_by(carrier) %>% summarize(mean(arr_delay, na.rm=TRUE)),
  times=50
)
mbm

library(ggplot2)
autoplot(mbm)