filter based on first letter in r code example

Example: using like filter dplyr

library(rbenchmark)
library(tidyverse)

# The data. Data expo 09. ASA Statistics Computing and Graphics 
# http://stat-computing.org/dataexpo/2009/the-data.html
df <- read_csv("Downloads/2008.csv")
print(dim(df))
# [1] 7009728      29

benchmark(
  "str_detect" = {df %>% filter(str_detect(Dest, 'MCO|BWI'))},
  "grepl" = {df %>% filter(grepl('MCO|BWI', Dest))},
  replications = 10,
  columns = c("test", "replications", "elapsed", "relative", "user.self", "sys.self"))
# test replications elapsed relative user.self sys.self
# 2      grepl           10  16.480    1.513    16.195    0.248
# 1 str_detect           10  10.891    1.000     9.594    1.281

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R Example