tidyverse1.R

storms_sum <- storms %>% 
  dplyr::filter(year %in% 1975:1977) %>% 
  dplyr::group_by(year, status) %>% 
  dplyr::summarise(mean = mean(pressure, na.rm = TRUE),
                   median = median(pressure, na.rm = TRUE))

storms_sum

#> # A tibble: 9 x 4
#> # Groups:   year [3]
#>    year status               mean median
#>   <dbl> <chr>               <dbl>  <dbl>
#> 1  1975 hurricane            977.   984 
#> 2  1975 tropical depression 1011.  1012.
#> 3  1975 tropical storm       992.   993 
#> 4  1976 hurricane            975.   975 
#> 5  1976 tropical depression 1007.  1006.
#> 6  1976 tropical storm       995.   994.
#> 7  1977 hurricane            978.   987 
#> 8  1977 tropical depression 1011.  1010 
#> 9  1977 tropical storm      1002.  1001