[R] newbie question: p.values in a column

[Uwe Ligges]

Hao Chen wrote:
> 
> Hello,
> 
> I have a vector (v) with 6 columns and 2000 rows. I am trying to do one
> sample t.test for each row (I know this sounds crazy) and put the
> p.values into the 7th column.
> 
> I know I can access the p.value via t.test(v[i,])[3]$p.value; I know I
> can do t.test on the row by apply(v, 1, t.test), but I just couldn't
> figure out how to fit them together.
> 
> I'd very appreciate your help!!

Whether it makes sense or not to perform a t.test() of your 6 numbers
...

I guess v is a matrix. In that case:

 # calculate the t.test() and extract p-values for each row:
 tt <- apply(v, 1, function(x) t.test(x)$p.value) 
 # put the tt values in a new column:
 v <- cbind(v, tt) 

Uwe Ligges
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