[R] Thanks to Mark, Henrique, and Jorge

Mark, Henrique, and Jorge, Thank you all very much for your replies. I'm really impressed by your knowledge of R: I'd never even heard of of some of these functions (especially split() and unlist().) I went with the Henrique-Mark solution and it is working fine. Thanks again! David

[R] Accesing data frame members from within functions

I am writing a simple R program to execute a t-test repeatedly on data contained in a data frame. My data looks like this: Category Value1 Value2 1 .5 .8 1 .3