[BioC] T-test error : not enough x observations.

[S Peri]

Hi all, 
 I am writing a T-test function for my hguav2 chip
analsys. I get the 
Error in t.test.default(xrow[cl == 0], xrow[cl == 1])
:  not enough x observations . error. 

What is wrong? can any one please suggest some
solution. 
Thank you. 
PS


>t.fx <- function(x,cl){
+ ttest2 <- function(xrow,cl){
+ return(t.test(xrow[cl==0],xrow[cl==1])$p.value)}
+ return(apply(x,1,ttest2,cl==cl))}
> pros.pvals <- t.fx(pro.exprs,prostate.cl)
Error in t.test.default(xrow[cl == 0], xrow[cl == 1])
: 
        not enough x observations