stephan.R

library(dplyr)

c(2, 5, 6) %>% sum()

cars_i_want <- mtcars %>%
  filter(mpg > 20) %>%
  filter(cyl == 4) %>%
  arrange(hp)

mtcars %>% 
  group_by(cyl) %>%
  summarize(avg_mpg = mean(mpg))

library(tibble)

subjects <- tribble(
  ~Name, ~Sex, ~Age,
  "Emily", "F", 22,
  "Stephan", "M", 25,
  "Sean", "M", 26
)

data <- data_frame(Name = sample(c(subjects$Name, "Bob"), 20, replace = TRUE),
                   Measurement = sample(1:10, 20, replace = TRUE))

data %>%
  left_join(subjects)

Links for joins:

• https://www.rstudio.com/wp-content/uploads/2015/02/data-wrangling-cheatsheet.pdf
• http://stat545.com/bit001_dplyr-cheatsheet.html