Thanks to Henry and Roger for help. it is written in system/extras/help/dictionary/d202n.htm b&#^:_1 where b is a boolean list is Expand (whose fill atom f can be specified by fit, b&#^:_1!.f)
I had read this page and this sentence before I asked, Why I failed to notice the portion inside parenthesis? (concentration dysfunction?) Also b&#^:_1 rather than b #^:_1 was mentioned, so that it does work without the & seems an extra bonus, is it reliable assuming fit is not needed? -- regards, bill ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
