[R] Need Help - Urgent

[Nivesh Pawar]

Hello,
I am a student and some really urgent help.I am using R software and while
creating a grid with eight elements its showing the error and while if i
do it with seven it says that the memory is not sufficient...
here is the line ...with the error....

> Z<-as.matrix(expand.grid(x,y,x,y,t,s,t,s))

Error in rep.int(rep.int(seq(length = nx), rep.int(rep.fac, nx)), orep) :
        cannot allocate vector of length 1128960000

Is it possible to somehow increase the default size of the matrix?
please help..

THanking you
nivesh pawar