[R] Conditional expand.grid()

[Hesen Peng]

Hello my R buddies,

I'm trying to generate a bivariate data.frame with the elements of
first row greater than the second row. The more complicated method
that I can think of is:

   n <- 10
   temp <- expand.grid(1:n,1:n)
   temp<-temp[temp[,1]>temp[,2],]

However, I guess there must be some easier way of doing this. Besides,
if inequality condition is applied at the very beginning, this will
save me a lot of memory if n goes to a very large number. Is there any
suggestions? Thanks a lot.

Best wishes,

-- 
彭河森 Hesen Peng
http://hesen.peng.googlepages.com/