That shows pretty clearly, in my opinion, which parenthesis are redundant, and why.
You'd need to compare it with the trace of the other expression to see the difference, of course. That said, Joe Bogner's post on how to see the intermediate results during an execution of that train gives another really good perspective: http://jsoftware.com/pipermail/programming/2014-July/038483.html Thanks, -- Raul On Sun, Jul 20, 2014 at 11:55 AM, Erling Hellenäs <erl...@erlinghellenas.se> wrote: > Yes, well, the trace: > > trace'3(***(***)(***))4' > --------------- 5 Trident ---- > > * > * > * > * * * > --------------- 8 Paren ------ > ( > * * * > ) > * * * > --------------- 5 Trident ---- > > * > * > * > * * * > --------------- 8 Paren ------ > ( > * * * > ) > * * * > --------------- 5 Trident ---- > > * > * * * > * * * > * (* * *) * * * > --------------- 5 Trident ---- > * > * > * (* * *) * * * > * * * (* * *) * * * > --------------- 8 Paren ------ > ( > * * * (* * *) * * * > ) > * * * (* * *) * * * > --------------- 2 Dyad ------- > 3 > * * * (* * *) * * * > 4 > 35831808 > ============================== > 35831808 > > > > /Erling > > > > On 2014-07-20 15:09, Joe Bogner wrote: >> >> This may also help show the evaluation more clearly: >> >> nb =: (;:^:_1) @: (":&.>) >> m=: 4 : 'x*y[smoutput nb y;''*'';x' >> >> 3 (m m m (m m m) m m m) 4 >> 4 * 3 >> 4 * 3 >> 12 * 12 >> 4 * 3 >> 144 * 12 >> 144 * 12 >> 1728 * 1728 >> 4 * 3 >> 2985984 * 12 >> 35831808 >> >> >> 3 ((m m m) (m m m) m m m) 4 >> 4 * 3 >> 4 * 3 >> 12 * 12 >> 4 * 3 >> 4 * 3 >> 12 * 12 >> 144 * 144 >> 144 * 144 >> 20736 * 20736 >> 429981696 >> >> >> >> On Sun, Jul 20, 2014 at 8:36 AM, Joe Bogner <joebog...@gmail.com> wrote: >> >>> I would explain it by quoting a few sentences from the dictionary >>> >>> Execution proceeds from right to left, except that when a right >>> parenthesis is encountered... in an unparenthesized expression the right >>> argument of any verb is the result of the entire phrase to its right... >>> The >>> executions in the stack are confined to the first four elements only >>> >>> I would then suggest that the person read the dictionary: >>> http://www.jsoftware.com/help/dictionary/dicte.htm >>> >>> And point to the pages on http://www.jsoftware.com/jwiki/Vocabulary/fork >>> and http://www.jsoftware.com/jwiki/Vocabulary/hook >>> >>> >>> And play with trace as Raul suggested >>> >>> >>> On Sun, Jul 20, 2014 at 12:13 AM, Linda Alvord <lindaalv...@verizon.net> >>> wrote: >>> >>>> But can you explain the difference in a few words? >>>> >>>> >> ---------------------------------------------------------------------- >> For information about J forums see http://www.jsoftware.com/forums.htm >> > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
