I need to subtract a number from a vector in such a way that it is subtracted serially from the elements. As an example, consider the vector a = c(8, 4). If I want to serially subtract 9 from this vector, I first subtract 9 from the first vector element, 8. That leaves 0 for the first element with a reminder of 1, that then gets subtracted from the second element. That leaves 4-1=3 for the second vector element.
I can do this with a bunch of inelegant if-else statement. There must be a better way. It would be easier to show examples:
I assume that the serial subtraction function is called serialSub.
a = c(8,4)
serialSub(a,4)
> [1] 4 4
serialSub(a,8)
> [1] 0 4
serialSub(a,9)
> [1] 0 3
serialSub(a,13)
> [1] 0 0
serialSub(a,0)
> [1] 8 4