r - More elegant way to return a sequence of numbers based on booleans? -

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here's sample of booleans have part of data.frame:

atest <- c(false, true, true, true, true, true, true, true, true, true, false, true, true, true, true, true, true, true, true, true, false)

i want return sequence of numbers starting @ 1 each false , increasing 1 until next false.

the resulting desired vector is: 

[1]  1  2  3  4  5  6  7  8  9 10  1  2  3  4  5  6  7  8  9 10  1

here's code accomplishes this, i'm sure there's simpler or more elegant way in r. i'm trying learn how code things more efficiently in r rather getting job done.

result <- c() x <- 1 for(i in 1:length(atest)){     if(atest[i] == false){         result[i] <- 1         x <- 1     }      if(atest[i] != false){         x <- x+1          result[i] <- x     } }

here's 1 way it, using handy (but not widely-known/used) base functions:

> sequence(tabulate(cumsum(!atest)))  [1]  1  2  3  4  5  6  7  8  9 10  1  2  3  4  5  6  7  8  9 10  1

to break down:

> # return/repeat integer each false > cumsum(!atest)  [1] 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 > # count number of occurrences of each integer > tabulate(cumsum(!atest)) [1] 10 10  1 > # create concatenated seq_len each integer > sequence(tabulate(cumsum(!atest)))  [1]  1  2  3  4  5  6  7  8  9 10  1  2  3  4  5  6  7  8  9 10  1

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