Doesn't u`v`:0 already give you this capability? Put different, I'm not yet convinced that V@(U/\.) -- where U=. u`v`:0 and V selects the result of u -- can be significantly more efficient than baking some special support for u and v into the fold implementation.
Part of this might be that I've yet to see any worked examples of how things are supposed to function? Part of this might be that I'm over optimistic about the efficiencies we can expect from boxed data structures? But, also, the current description of the proposed F:: series of conjunctions makes it sound an awful lot like what's being proposed would offer behavior exactly like v@u/\. So maybe what I'm really groping for here is a clearer explanation of the proposal? (With some hints, here, about where I think this could lead...) Thanks, -- Raul On Fri, Mar 2, 2018 at 10:40 AM, Henry Rich <henryhr...@gmail.com> wrote: > Suppose I am running some simulation that has a state vector S. At every > step my verb u takes an input from the input list and produces an output > atom and a new state vector. > > The key points: each execution of u needs the modified state vector; the > desired result comprises the output atoms from each execution of u, but not > the state vectors. > > v@u/\. is inadequate: v extracts the output atom, but the state vector is > not passed to the next execution of u. > > v@(u/\.) is inefficient: all the intermediate copies of the state vector > are included in the result of u/ . > > Henry Rich > > On 3/2/2018 9:55 AM, Raul Miller wrote: >> >> I don't understand this thinking: >> >> [1] It seems like v@(...) should work just fine to extract relevant >> state from a larger bag of state. >> >> [2] The proposal used v every step of the way rather than as the final >> stage. >> >> Is there some good example that shows how using v every step of the >> way solves the "simplify the final state" issue? >> >> Thanks, >> > > > --- > This email has been checked for viruses by AVG. > http://www.avg.com > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
