Applying function on rolling window basis ** not rollapply() function in zoo

Hi all, in the zoo package there is a function rollapply() to apply some
fixed function on rolling window basis. I am looking for some same sort of
function on **temporal sampling basis** means, I would like to apply a
function say mean() for data window of length 30 like observations for 1:30,
31:60, . so on.



Is there any facility to doing that directly?

library(zoo)
z <- zoo(1:9)
rollapply(z, 3, by = 3, mean)