Mike Day had said:

> However my actual values for count get very large,
> ie up to 2^50 or more, and I needed exact integer results

where "count" is the right argument n that we are talking about.
Consider:

   (1000$0) x:@+//. 1000$2^50
1125899906842623744
   (1000$0) +//. x: 1000$2^50
1125899906842624000
   (1000$0) +//. 1000$2^50x
1125899906842624000

"adding a 0 on the right end of the list":

   (1000$0) x:@+//.&(,&0) 1000$2^50
1125899906842623744

I stand by what I said about not achieving the intent.



----- Original Message -----
From: Raul Miller <[EMAIL PROTECTED]>
Date: Friday, September 28, 2007 11:25
Subject: Re: [Jprogramming] Performance of exact keyed aggregate
To: Programming forum <[email protected]>

> On 9/28/07, Roger Hui <[EMAIL PROTECTED]> wrote:
> > v x:@+//. n  is a curious phrase and does not achieve the 
> intent> expressed in your msg.
> 
> As long as the initial integer pair does not overflow (if this 
> is a problem,
> it could be easily achieved by adding a 0 on the right end of 
> the list),
> x:@+/ would seem to me to achieve the expressed intent.
> 
> Additionally, x:@+/ has significantly lower memory requirements than
> +/@x:
> 
> That said, +&x:/ might be clearer than x:@+/
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