How to find the indices where there are n consecutive zeroes in a row

Question

Suppose I have this data:

  x = c(14,14, 6,  7 ,14 , 0 ,0  ,0 , 0,  0,  0 , 0 , 0,  0 , 0 , 0 , 0,  9  ,1 , 3  ,8  ,9 ,15,  9 , 8, 13,  8,  4 , 6 , 7 ,10 ,13         


        

Answer 1

Starts = which(diff(x == 0) == 1) + 1
Ends   = which(diff(x == 0) == -1)
if(length(Ends) < length(Starts)) {
    Ends = c(Ends, length(x)) }

Starts
[1]  6 34 72
Ends
[1] 17 58 89

This works for your test data, but allows any sequence of zeros, including short ones. To insure that you get sequences of length at least n, add:

n=3
Long = which((Ends - Starts) >= n)
Starts = Starts[Long]
Ends = Ends[Long]