Separate positive values into multiple rows on multiple columns

Question

Suppose I have a data set like this:

dat <- tibble(id = 1:4, 
              col1 = c(0, 1, 1, 0),
              col2 = c(1, 0, 1, 0),
              col3 = c(1, 1, 0, 1))

> dat
# A tibble: 4 × 4
     id  col1  col2  col3
  <int> <dbl> <dbl> <dbl>
1     1     0     1     1
2     2     1     0     1
3     3     1     1     0
4     4     0     0     1

I'd like to separate, for every unique id, the multiple 1s into multiple rows, i.e. the expected output is:

# A tibble: 7 × 4
     id  col1  col2  col3
  <dbl> <dbl> <dbl> <dbl>
1     1     0     1     0
2     1     0     0     1
3     2     1     0     0
4     2     0     0     1
5     3     1     0     0
6     3     0     1     0
7     4     0     0     1

For the first id (id = 1), col2 and col3 are both 1, so I would like a separate row for each of them. It kinda is like one-hot encoding for rows.

Answer 1

With help from Ritchie Sacramento and RobertoT

library(tidyverse)

dat <- tibble(id = 1:4, 
              col1 = c(0, 1, 1, 0),
              col2 = c(1, 0, 1, 0),
              col3 = c(1, 1, 0, 1))

dat %>%  
  pivot_longer(-id) %>% 
  filter(value != 0) %>% 
  mutate(rows = 1:nrow(.)) %>% 
  pivot_wider(values_fill = 0, 
              names_sort = TRUE) %>% 
  select(-rows)

# A tibble: 7 × 4
     id  col1  col2  col3
  <int> <dbl> <dbl> <dbl>
1     1     0     1     0
2     1     0     0     1
3     2     1     0     0
4     2     0     0     1
5     3     1     0     0
6     3     0     1     0
7     4     0     0     1