> Did you check the factorised result on mac32 was correct? Hahaha! No I didn't. It isn't.
I'd only checked it factorised the extended value : 576460752303423487x But of course it shouldn't be expected to under j32, because (2^59)-1 is not represented exactly ... z=: 576460752303423487 z 5.76461e17 z=z-1 1 I was misled by Eugene's statement in: http://www.jsoftware.com/jwiki/Doc/Articles/Play103 "The argument must be a positive integer not greater than max, where max is a number derived from the floating-point characteristics of your computer. This discussion assumes that your computer uses IEEE floating point arithmetic, which is the case for PCs, Macintoshes, and most Unix machines. On PCs and Unix machines the maximum is the 16-digit integer (2^53)-1 (9007199254740991). For Macintoshes it is the 19-digit (2^63)-1 (9223372036854775807), or 1024 times as large. These are the largest integers which can be represented to full accuracy on the hardware of those machines." I've just tried the following... JVERSION Engine: j701/2011-01-10/11:25 Library: 7.01.042 Platform: Darwin 32 Installer: j701a_mac_intel.dmg InstallPath: /Applications/j701 maxint=: 3 : 0 z=. 2^y-1 z+(z-1) ) maxint 16 65535 (z-1) = z=: maxint 44 0 (z-1) = z=: maxint 45 1 ---- JVERSION Engine: j701/2011-01-10/11:25 build: Feb 6 2011 16:16:29 Library: 7.01.043 Platform: Darwin 64 Installer: j701a_mac64.dmg InstallPath: /Applications/j64-701 (z-1) = z=: maxint 44 0 (z-1) = z=: maxint 45 1 ...no different. (Why should I be surprised at that?) On Tue, Feb 8, 2011 at 2:58 AM, bill lam <[email protected]> wrote: > You are lucky, I tried on linux64, it just hanged and can only press reset > key to reboot. > > Did you check the factorised result on mac32 was correct? > > Втр, 08 Фев 2011, Ian Clark писал(а): >> Thanks from me too, on behalf of the Mac community. Like Charles, >> couldn't wait to try it out. >> >> But I ought to report this... >> >> Hoping to show-off the difference between 32 and 64 bit, I thought I'd >> replicate the timings of p17 of At Play With J ... >> http://www.jsoftware.com/jwiki/Doc/Articles/Play103 >> >> factors=: 3 : 0 >> f=. i. 0 >> t=. 2 3 5 7 11 13 17 19 23 29 31 37 >> o=. +/\ 432 $ 4 2 4 2 4 6 2 6 >> whilst. y >: *: {. t do. >> whilst. #m do. >> m=. (-. * t |!.0 y) # t >> f=. f , m >> y=. y % */ m >> end. >> t=. o + {: t >> end. >> /:~ f , y -. 1 >> ) >> >> smoutput 0 : 0 >> NB. TRY ... >> factors 576460752303423487x NB. (2^59)-1 extended precision >> NB. should respond with: 179951 3203431780337 >> 6!:2 'factors 576460752303423487x' >> 6!:2 'factors 576460752303423487' >> ) >> >> ---- >> >> JVERSION >> Engine: j701/2011-01-10/11:25 >> Library: 7.01.042 >> Platform: Darwin 32 >> Installer: j701a_mac_intel.dmg >> InstallPath: /Applications/j701 >> >> 6!:2 'factors 576460752303423487x' >> 1.42849 >> 6!:2 'factors 576460752303423487' >> 0.00021698 >> >> ---- >> >> JVERSION >> Engine: j701/2011-01-10/11:25 build: Feb 6 2011 16:16:29 >> Library: 7.01.043 >> Platform: Darwin 64 >> Installer: j701a_mac64.dmg >> >> InstallPath: /Applications/j64-701 >> >> 6!:2 'factors 576460752303423487x' >> 1.19236 >> 6!:2 'factors 576460752303423487' >> ... lots of disk activity, no reponse. Force Quit after 1 min. >> ...Tried it twice. >> ---------------------------------------------------------------------- >> For information about J forums see http://www.jsoftware.com/forums.htm > > -- > regards, > ==================================================== > GPG key 1024D/4434BAB3 2008-08-24 > gpg --keyserver subkeys.pgp.net --recv-keys 4434BAB3 > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
