Sum rows by group with condition in R

Question

I have a dataset in R like this one:

and I want to keep the same dataset with adding a column that gives the sum rows by ID when A=B=1.

This is the required dataset:

I tried the following R code but it doesn't give the result I want:

library(dplyr)

data1<-data%>% group_by(ID) %>% 
  mutate(result=case_when(A==1 & B==1 ~ sum(A),TRUE ~ 0)) %>% ungroup()

Answer 1

Not as neat and clean , but still:

data %>%
  mutate(row_sum = apply(across(A:B), 1, sum)) %>%
  group_by(ID) %>%
  mutate(result = sum(row_sum == 2)) %>%
  ungroup() %>%
  select(-row_sum)

which gives:

# A tibble: 10 x 4
      ID     A     B result
   <dbl> <dbl> <dbl>  <int>
 1     1     1     0      3
 2     1     1     1      3
 3     1     0     1      3
 4     1     0     0      3
 5     1     1     1      3
 6     1     1     1      3
 7     2     1     0      2
 8     2     1     1      2
 9     2     1     1      2
10     2     0     0      2

Answer 2

After grouping by 'ID', multiply the 'A' with 'B' (0 values in B returns 0 in A) and then get the sum

library(dplyr)
data  %>%
     group_by(ID) %>%
     mutate(result = sum(A*B)) %>%
     ungroup

-output

# A tibble: 10 × 4
      ID     A     B result
   <dbl> <dbl> <dbl>  <dbl>
 1     1     1     0      3
 2     1     1     1      3
 3     1     0     1      3
 4     1     0     0      3
 5     1     1     1      3
 6     1     1     1      3
 7     2     1     0      2
 8     2     1     1      2
 9     2     1     1      2
10     2     0     0      2

data

data <- structure(list(ID = c(1, 1, 1, 1, 1, 1, 2, 2, 2, 2), A = c(1, 
1, 0, 0, 1, 1, 1, 1, 1, 0), B = c(0, 1, 1, 0, 1, 1, 0, 1, 1, 
0)), class = "data.frame", row.names = c(NA, -10L))