Remove rows with a unique value in one column? Help

General
2

See the FAQ: How to do a minimal reproducible example reprex for beginners.

Something like this

library(dplyr)

counts <- DF %>% filter(ccode ==  2 | ccode = 710) %>% group_by(dispnumb) %>% count()
dupes <- counts > 2
DF2 <- DF %>% filter(dispnumb %in% dupes) %>% filter(ccode != 2 | 710)

This may not work because it was not run against data.