I want to create a dummy variable that takes the value 1 if either variable a has a value between 300 and 400 or if value b has a value 1. Only one of these would need to be fulfilled, I.e. variable a could be outside the range, but b=1, the dummy would still be 1. Is there any way to compute this? I can't find any way (even in the fast dummies package, to my understanding) to incorporate both of these.