r - How to specify "does not contain" in dplyr filter

Question

I am quite new to R.

Using the table called SE_CSVLinelist_clean, I want to extract the rows where the Variable called where_case_travelled_1 DOES NOT contain the strings "Outside Canada" OR "Outside province/territory of residence but within Canada". Then create a new table called SE_CSVLinelist_filtered.

SE_CSVLinelist_filtered <- filter(SE_CSVLinelist_clean, 
where_case_travelled_1 %in% -c('Outside Canada','Outside province/territory of residence but within Canada'))

The code above works when I just use "c" and not "-c".
So, how do I specify the above when I really want to exclude rows that contains that outside of the country or province?

Answer 1

Note that %in% returns a logical vector of TRUE and FALSE. To negate it, you can use ! in front of the logical statement:

SE_CSVLinelist_filtered <- filter(SE_CSVLinelist_clean, 
 !where_case_travelled_1 %in% 
   c('Outside Canada','Outside province/territory of residence but within Canada'))

Regarding your original approach with -c(...), - is a unary operator that "performs arithmetic on numeric or complex vectors (or objects which can be coerced to them)" (from help("-")). Since you are dealing with a character vector that cannot be coerced to numeric or complex, you cannot use -.