Is there an easy way to find the smallest positive integer k such that (u^:(k-1) y) -: u^:k y ? I know that for simple cases it is <:# u^:(<_) y or thereabouts.
If the argument gets its shaped changed by u, I find myself writing things like <: # u&.>^:(<_) < y which is fine so long as the intermediate results are small. If they are large, I do u&.>^:(<_) by hand, except I zap the contents of all but the last box, so that I am essentially using empty boxes to count. While this works, it feels wrong. Can anyone tell me how to do it properly? Thanks. Best wishes, John ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
