I'd be tempted by +/+:^:(i.63)1 9223372036854775807 Or, even better:
#.63#1 9223372036854775807 And, of course: 3!:0+/+:^:(i.63)1 4 3!:0#.63#1 4 Thanks, -- Raul On Mon, May 26, 2014 at 2:35 PM, 'Pascal Jasmin' via Programming < [email protected]> wrote: > Might this be the fastest way of getting 2^63-1, without x: ? > > (<: + ] ) +:^:14 *:^:4 ] 8 > 9223372036854775807 > > worth noting: > > +:^:62 ] 2 > 9.22337e18 > +:^:61 ] 2 > 4611686018427387904 > > 2 <: &. x:@^ 63 > 9223372036854775807 > > > --- > actually this is probably best: > > 2 <: &. x:@^ 63 > 9223372036854775807 > 3!:0 ] 2 <: &. x:@^ 63 > 4 > > > > > ----- Original Message ----- > From: Raul Miller <[email protected]> > To: Programming forum <[email protected]> > Cc: > Sent: Monday, May 26, 2014 2:02:01 PM > Subject: Re: [Jprogramming] 2^63 > > Here's an interesting bug (I can't call this kind of issue a feature if > it's not documented in the dictionary, can I?): > > 9223372036854775809 > 9223372036854775807 > > (And that's probably more important than the "using ^" issue.) > > Thanks, > > -- > Raul > > > > > > > On Mon, May 26, 2014 at 1:55 PM, 'Pascal Jasmin' via Programming < > [email protected]> wrote: > > > is there a way to get ^ to make a 64bit number without it being extended > > precision? I guess an efficient alternative to ^ if that is not > possible: > > > > 2^63 > > 9.22337e18 > > 2^63x > > 9223372036854775808 > > 9223372036854775808 > > 9223372036854775807 > > > > Note that the last line is probably a problem. The answer is the largest > > non extended integer, but still unwelcome change from the input. > > > > 9223372036854775808-1 > > 9223372036854775806 > > 9223372036854775809-1 > > 9223372036854775806 > > > > I guess this works > > > > (<: + ] ) 4611686018427387904 > > NB. 2^62x > > 9223372036854775807 > > > > ---------------------------------------------------------------------- > > For information about J forums see http://www.jsoftware.com/forums.htm > > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
