> Are not Atop and At both able to keep, or alter, the rank at which an > argument verb is applied? I think whether rank is changed depends on the > rank of the verb.
@: (or &:) is said to produce a verb of infinite ranks (of which, here, we are only interested in the monadic case). As I understand it, this can only be achieved by modifying the ranks of the arguments and/or the rank of the result. Whatever it is, @: is different from @. Therefore, if f@g (again, monadic) is the composition in the usual mathematical sense (as asserted in the DoJ), then f@:g is not it. ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
