I have the following data frame

I want to eliminate the data with its counterpart conditioned to the ID and that it looks like this:

I have tried to put it in absolute values and leave the value that is unique, but this can produce an error if both are negative and should not be eliminated.

CodePudding user response：

df %>%
  mutate(abs_neto=abs(neto)) %>%
  group_by(damo,abs_neto) %>%
  mutate(one_plus_one_minus= any(neto>=0) & any(neto<=0))%>%
  filter(n()==1 | !one_plus_one_minus)%>%
  ungroup 

   neto  damo abs_neto one_plus_one_minus
  <int> <int>    <int> <lgl>             
1  -175     9      175 FALSE             
2   250     9      250 FALSE             
3   250     9      250 FALSE

CodePudding user response：

We may group by 'damo', remove the groups having only a single absolute 'neto' value, grouped by absolute of 'neto', filter out the groups having one value

library(dplyr)
df1 %>%
   mutate(s1 = sign(neto), absneto = abs(neto)) %>% 
   arrange(damo, desc(absneto), s1 == -1) %>% 
   group_by(damo) %>% 
   mutate(grp = cumsum(s1 > 0)) %>% 
   group_by(grp, .add = TRUE) %>% 
   filter(n_distinct(absneto) > 1|n_distinct(s1) == 1) %>% 
   group_by(s1, .add = TRUE) %>% 
   summarise(neto = sum(neto), .groups = "drop") %>%   
   select(-grp, -s1)

-output

# A tibble: 3 × 2
   damo  neto
  <int> <int>
1     9  -175
2     9   250
3    18  -108

data

df1 <-structure(list(neto = c(356L, -356L, -175L, 700L, -700L, 250L, 
-36L, -36L, -36L), damo = c(8L, 8L, 9L, 9L, 9L, 9L, 18L, 18L, 
18L)), class = "data.frame", row.names = c(NA, -9L))