> 
> 
> I am new to this group - joined today. I am in because i have an assignment to do using R => microarray analysis using affy (bioconductor). 
> 
> while reading some tutorials, i came across this and i am stuck. i want to understand it and would appreciate if anyone can tell me. 
> 
> design <- model.matrix(~ -1+factor(c(1,1,2,2,3,3)))
> 
> can someone break down this code and explain to me what the "~", and the "-1+factor" are doing? sometimes i see codes without some of these things. 
> 
> thanks, would appreciate if you can explain it in the simplest way you can. i am a pure molecular biologist and trying to learn this new monster called R. :-) 
> 
> thanks, 
> 
> daniel


	[[alternative HTML version deleted]]

