That was my original impression. But then I looked at the right hand side of the expression:
Why is it labelled x,y,:z and why does the text mention the case c}x,y,...,:z? It might be that this was originally a more ambitious project and that Roger got interrupted before he finished it. Anyways, it is interesting to me that the wiki page is silent about this explicitly documented issue. -- Raul On Thu, Aug 7, 2014 at 8:53 AM, Henry Rich <[email protected]> wrote: > 'boolean' here means that 3!:0 returns 1; the values are restricted to > {0,1}. Details at > > http://www.jsoftware.com/jwiki/Vocabulary/SpecialCombinations# > Assignments_In_Place_.28AIP.29 > > > Henry Rich > > > On 8/7/2014 8:42 AM, Raul Miller wrote: > >> I think http://jsoftware.com/help/release/iamend.htm might be relevant. >> >> Note also that in this case I'm not sure if "boolean" really means >> "non-negative integer". (If I understand properly: in George Boole's >> arithmetic these were equivalent, and some of the details here suggest >> that >> that original meaning might be relevant here. It's a confusing topic >> though >> because it has become popular, depending on context, to assert that >> "boolean" can only refer to the values 0 and 1 and also that "boolean" >> cannot be used to refer to the values 0 and 1.) >> >> Thanks, >> >> ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
