Conformability IS required in your example, but with the left rank of v (, in this case) being infinite, everything conforms.
(BTW, your verb is (+/ .,)/ , which is not necessarily the same as +/ . (,/) .) ----- Original Message ----- From: Devon McCormick <[email protected]> Date: Monday, February 22, 2010 7:56 Subject: Re: [Jprogramming] Generalized Matrix Multiplication To: Programming forum <[email protected]> > I see my comment about conformability was too specific to matrix > multiplication. I see from Roger's comment that we should > consider the more > general case for what constitutes conformability. I'll > have to think of a > more practical example, but here's one for conformability that > does not > require the inner dimensions to match: > > (i.3 4) +/ . ,/ i.5 5 > 62 70 78 86 70 > > On Mon, Feb 22, 2010 at 10:42 AM, Roger Hui <[email protected]> > wrote: > > ... > > For general u . v the conformability requirements depend > > on the left rank of v and the shape of the result depend > > on the shapes of results produced by u and v , as > > the definition u . v <-> u@(v"(1+lv,_)) would indicate. > > ... ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
