[rscho]

I disagree. For the stuff I'm doing, I've been rewriting the same 1-screen program in different ways many times. J made that easy, R would make that much more tedious since I'd have >250 lines instead of 30. Of course if I'm doing something for which R has libs, I'll do it in R. Additionally, I'll very probably end up rewriting my final program in another language for speed and libs, because by then I'll know precisely what I want to write. IMO, the strength of array languages lies in easy experimentation.

[nathan_compton]

I think there is an element of truth to this, but the context where this ends up being an advantage is personal and idiosyncratic.