I want to find duplicated elements and flag them in a rolling window. Does anyone know how to do it in r? For example, assume that I want to check whether value is repeated in the following 2 rows. I want to get something like this:
| row_number | value | flag |
|---|---|---|
| 1 | 2 | TRUE |
| 2 | 2 | FALSE |
| 3 | 1 | FALSE |
| 4 | 3 | FALSE |
| 5 | 2 | TRUE |
| 6 | 6 | FALSE |
| 6 | 2 | FALSE |