Selecting a group of rows if one of them has a desired attribute

Question

I have a data frame like this:

data <- data.frame(family.id=rep(1:6, each=5), 
                   member.id=rep(1:5, times=6), 
                   attribute=c(1, 1, 2, 3, 4, 1, 2, 2, 3, 5, 1, 1, 3, 5, 5, 2, 
                               3, 3, 4, 5, 1, 1, 4, 4, 5, 3, 3, 4, 5, 5))

I want to select all household members, if at least one of them has an attribute equal to 4. please tell me what should i do?

I prefer to use the "group_by" command from dplyr.

Answer 1

library(tidyverse)

data %>% 
      filter(any(attribute == 4), .by = family.id)

or

data %>% 
  group_by(family.id) %>% 
  filter(any(attribute == 4)) %>% 
  ungroup()

   family.id member.id attribute
1          1         1         1
2          1         2         1
3          1         3         2
4          1         4         3
5          1         5         4
6          4         1         2
7          4         2         3
8          4         3         3
9          4         4         4
10         4         5         5
11         5         1         1
12         5         2         1
13         5         3         4
14         5         4         4
15         5         5         5
16         6         1         3
17         6         2         3
18         6         3         4
19         6         4         5
20         6         5         5