Comment by xsg

"They're both designed around completely in-memory arrays, which are passed around by-value with a copy-on-write scheme." True, but that doesn't invalidate my point. The datasets I'm typically working with are quite large 300GB-1TB (I have 2TB ram on my main server). I've tried both R and MATLAB and R has been a disaster. Even to plot say 10 million points on a graph is a pain.