weird summarise

werid.R

``` r
library(tidyverse)

fruits <- tribble(~fruit, ~date, ~sold,
                  "Apple", "2020-06-23", 1,
                  "Apple", "2020-06-24", 2) %>%
  mutate(fruit = fct_expand(fruit, "Banana"))

levels(fruits$fruit)
#> [1] "Apple"  "Banana"

fruits %>%
  group_by(fruit, .drop = FALSE) %>%
  summarise(weird = sum(sold) / 1)
#> `summarise()` ungrouping output (override with `.groups` argument)
#> # A tibble: 2 x 2
#>   fruit  weird
#>   <fct>  <dbl>
#> 1 Apple      3
#> 2 Banana     0

fruits %>%
  group_by(fruit, .drop = FALSE) %>%
  summarise(weird = 1 / sum(sold))
#> `summarise()` ungrouping output (override with `.groups` argument)
#> # A tibble: 2 x 2
#>   fruit    weird
#>   <fct>    <dbl>
#> 1 Apple    0.333
#> 2 Banana Inf

fruits %>%
  group_by(fruit, .drop = FALSE) %>%
  summarise(weird = max(sold))
#> Warning in max(sold): no non-missing arguments to max; returning -Inf
#> `summarise()` ungrouping output (override with `.groups` argument)
#> # A tibble: 2 x 2
#>   fruit  weird
#>   <fct>  <dbl>
#> 1 Apple      2
#> 2 Banana  -Inf
```

<sup>Created on 2020-06-23 by the [reprex package](https://reprex.tidyverse.org) (v0.3.0)</sup>