| Fish_ID | Instance | Success | First_Success | Inst_Diff |
|---|---|---|---|---|
| 1 | 0 | 0 | 0 | -2 |
| 1 | 1 | 0 | 0 | -1 |
| 1 | 2 | 1 | 1 | 0 |
| 1 | 3 | 0 | 0 | 1 |
| 1 | 4 | 1 | 0 | 2 |
| 1 | 5 | 0 | 0 | 3 |
results %>%
group_by(Fish_ID) %>%
mutate(Inst_Diff = Instance- Instance[First_Success==1])
I want to create a Inst_Diff column. Using instance number where the first success equals to 1 then the ‘Inst_Diff’ is equivalent to: (Instance) - (Instance at at first success). I have more than one Fish_ID. I tried to code above but it gives an error. I would appericate your suggestions. Thank you!
An approach using first
library(dplyr)
df %>%
mutate(Inst_Diff = Instance - first(Instance[Success == 1]), .by = Fish_ID)
Fish_ID Instance Success First_Success Inst_Diff
1 1 0 0 0 -2
2 1 1 0 0 -1
3 1 2 1 1 0
4 1 3 0 0 1
5 1 4 1 0 2
6 1 5 0 0 3