How to filter not %in%?

Question

I have a dataframe df with an ID column. I use the following code to filter the values of df contained in a vector of ID:

df <- df %>% 
  filter(ID %in% vector)

How can I filter to get all the df values that have ID not contained in vector instead than contained in vector?

Answer 1

Use ! to invert a condition:

df <- df %>% 
  filter(! ID %in% vector)

Answer 2

Arguably, the most elegant solution is achieved by leveraging functional programming capabilities available in R and using Negate to create a %nin% function that will return results reverse to those that the already available %in% provides.

library("tidyverse")
`%nin%` <- Negate(`%in%`)
mtcars %>%
  filter(cyl %nin% c(6, 4))
#>                      mpg cyl  disp  hp drat    wt  qsec vs am gear carb
#> Hornet Sportabout   18.7   8 360.0 175 3.15 3.440 17.02  0  0    3    2
#> Duster 360          14.3   8 360.0 245 3.21 3.570 15.84  0  0    3    4
#> ... (truncated for brevity)

^{Created on 2022-04-07 by the reprex package (v2.0.1)}

If you are working in tidyverse you may want to consider using negate. Tidyverse functions play nicely with each other and usually there subtle differences in implementation¹

library("tidyverse")
`%nin%` <- negate(`%in%`)
mtcars %>%
  filter(cyl %nin% c(6, 4))
#>                      mpg cyl  disp  hp drat    wt  qsec vs am gear carb
#> Hornet Sportabout   18.7   8 360.0 175 3.15 3.440 17.02  0  0    3    2
#> Duster 360          14.3   8 360.0 245 3.21 3.570 15.84  0  0    3    4
#> ... (truncated for brevity)

^{Created on 2022-04-07 by the reprex package (v2.0.1)}

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¹Functionals, Advanced R.