To me the First big distinction between @s and &s is the fact that v is executed dyadically with @ and monadically with &. This is likely suggested by the width of the rectangles especially at the bottom of the diagram, but it is not stated there, in favor of the phrase about each cell. But the each (result, sometimes) cell issue is the same everywhere. To me the Second big distinction between :s and no:s is the collection/supply sequence at the top of the page. On the other hand, nothing on the page tells me how to differentiate red from blue arrows (no, now I see that the sequencing of collection/supply explains the difference between blue and red arrows), ellipses from blue and black rectangles. So I'm thinking a possible addition would be a legend or symbol list and a note to notice the sequence difference between : and no: .
I look forward to other explanations, too. -- (B=) ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
