如何使用R从与另一列中的ID相关联的一系列列中仅选择特定的唯一值

Question

ID conditionA conditionB conditionC
1    1            0       0
1    0            0       1
1    0            0       0
2    1            0       1
2    0            1       0
3    1            0       1
3    0            1       0
3    1            1       0

in the picture above, I want for each ID only single value of each condition, making it a single row for each ID. This way I can have one row for each ID and under each condition a 1 or 0. Thanks

Answer 1

This can be easily done by using the dplyr package.

library(dplyr)

data %>%
  group_by(ID) %>%
  summarize(
    conditionA = max(conditionA), 
    conditionB = max(conditionB),
    conditionC = max(conditionC)
  )

The group_by() will group by ID , then the summarize() fnction will coalesce all rows under that ID to a single one. conditionA will assume the maximum value found in all rows for that ID, that is, if a 1 is present, then it will be one; if only 0s are present, then the maximum will be zero. Same for conditionB , and conditionC .