Here's what I get from J602: 9223372036854775808 9.22337e18 3!:0]9223372036854775808 8
Here's what I get from J64-602: 9223372036854775808 9223372036854775807 3!:0]9223372036854775808 4 Thanks, -- Raul On Mon, May 26, 2014 at 4:28 PM, 'Bo Jacoby' via Programming < [email protected]> wrote: > I get this using j602. It seems to be correct. > > 2^63 > 9.22337e18 > > > 2^63x > 9223372036854775808 > > > 9223372036854775808 > 9.22337e18 > > > 9223372036854775808x > 9223372036854775808 > > > > > > Den 21:23 mandag den 26. maj 2014 skrev Raul Miller <[email protected] > >: > > > > > > > >I'm not sure that execution time is a significant bottleneck here. > > > >If it is, though, I don't think you can get much faster than: > > 10000 timespacex '9223372036854775807' > >7.18584e_7 1408 > > > >That said, Henry's approach is about the same speed: > > 10000 timespacex '33 b.~_1' > >7.46583e_7 1920 > > > >And if what you want is platform specific (different on 32 bit J from 64 > >bit J), Henry's approach would probably be the right way. > > > >That said, I still like this: > > 10000 timespacex '#.63#1' > >7.71728e_7 1664 > > > >Maybe I'm just a sucker for polynomial representations? > > > >Thanks, > > > >-- > >Raul > > > > > > > >On Mon, May 26, 2014 at 3:07 PM, 'Pascal Jasmin' via Programming < > >[email protected]> wrote: > > > >> The 2 fastest versions I've found on my computer: > >> > >> 100 timespacex '( + <: ) */ +:@:*:^:2 ] 1024 16' > >> 3.4112e_6 4352 > >> > >> 100 timespacex '(+ <:) +:^:14 *:^:4 ] 8 ' > >> 5.5744e_6 3072 > >> > >> > >> The &. x: is obviously much more generic and practical for generating > >> "medium" sized numbers. > >> > >> 100 timespacex ' 2 <: &. x:@^ 63 ' > >> 8.064e_6 5632 > >> > >> > >> The importance of all this, btw, is that there is a significant size > >> penalty to storing extended integers, as well as a time/space > compromise in > >> working with them. > >> > >> > >> > >> ----- Original Message ----- > >> From: 'Pascal Jasmin' via Programming <[email protected]> > >> To: "[email protected]" <[email protected]> > >> Cc: > >> Sent: Monday, May 26, 2014 2:35:14 PM > >> Subject: Re: [Jprogramming] 2^63 > >> > >> 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 > >> > >---------------------------------------------------------------------- > >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
