The correct way is to compute all the terms in the expression and then multiply them together. Something like n* > *&.>/ >:@i.&.> n->:i.k However, the expressions you gave will return length errors, since (>:i.n-2) is patently not the same length as (>:i.n-1). What exactly are you trying to compute?
Marshall On Wed, Oct 19, 2011 at 10:39 AM, David Vaughan < [email protected]> wrote: > I couldn't really think of an appropriate title for this. My issue is that > I want to compute an expression that has a different number of terms > depending on y. > > +/(>:i.n-1)*n NB. for all n, y >: n > 1 > +/(>:i.n-2)*(>:i.n-1)*n NB. for all n, y >: n > 2 > > and so on, so that: > > lim =. <:<.y%2 > > and we carry on the style of expression above until we are doing it for all > n, y >: n > lim. > > So in the case for y=.5, lim=.1 and we only do the first of the lines > above. For y=.7, we would do the second one as well. For y=.9 we would do > the same as the second but with a (>:i.n-3) multiplied with it all as well. > I guess/hope there is some way of achieving this with power? > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
