Consider a python dataframe
A B C
1 random imp1
2 random imp2
5 random imp3
1 yes ---
2 yes ---
3 no ---
4 no ---
5 yes ---
Whenever column B has a value yes, I want to fetch values of A. And eventually for those values of A, I want C when those values occurred 1st in A. So in this case, I finally want imp1, imp2 and imp3.
Is there an elegant way of doing this.