Thanks you,

I can get the length of aa with length(unlist(aa)). If aa has 4 dimensions, I imagine I'd need to do

max(sapply(aa,sapply,sapply,length)

How can I do this in a generic way? That is in a loop. I am clear about the exit condition for the loop.

d<-1


start loop

if d = length(unlist(aa)) then exit loop 

else
    d<-d * <expr>


How do I construct <expr> such that it does  

> d<- d * length(aa)                      # first pass

> d<- d * max(sapply(aa, length))         # second pass

> d<- d * max(sapply(aa, sapply, length)) # third pass


> # ? #                                    # fourth path etc 


(Apologies for the pseudo code describing the loop; I am not near a machine with R)

One way I can thing of is to create a loop counter variable, say lc<-1 and to increment it within the loop and then use a switch statement to execute the appropriate expression. This sems like a kludge to me.

Is there a neater way?

	[[alternative HTML version deleted]]