Since using , to build boxed arrays does not currently have any code to support it, time is O(n^2). In other words: inefficient for long lists of boxes.
So let's say we wanted to build lists of 30000 boxes, how could we do that efficiently? It seems to me that the right thing to do would be: pick a threshold (maybe 1000 boxes) and when your list gets that long, append that intermediate result to a result list and start a fresh instance of the working list. Repeat until done (and don't forget to append the last intermediate list to the result). Conceptually speaking, this is still O(n^2). But it should also be orders of magnitude faster (at the cost of some complexity) than use of unadorned comma. (And conceptually speaking one might be able to define some kind of "infinite" representation of this algorithm which has better than O(n^2) performance. Maybe O(n log n)? Thanks, -- Raul ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
