I never managed to run j701. I only get the DOS-screen j701con rather than in J602 where I get a windows screen 1.ijx. How do I proceed?
>________________________________ >Fra: Roger Hui <[email protected]> >Til: Programming forum <[email protected]> >Sendt: 18:41 lørdag den 29. oktober 2011 >Emne: Re: [Jprogramming] 32- & 64-bit PRNGs > >Yes, the examples I gave require J7.01 to work. > > > >On Sat, Oct 29, 2011 at 9:14 AM, Bo Jacoby <[email protected]> wrote: >> In J602 I get >> ^o.j.-:i. 3 4 >> 1 6.12323e_17j1 _1j1.22465e_16 _1.83697e_16j_1 >> 1j_2.44929e_16 3.06162e_16j1 _1j3.67394e_16 _4.28626e_16j_1 >> 1j_4.89859e_16 5.51091e_16j1 _1j6.12323e_16 _2.44991e_15j_1 >> >> >> >> >> >>>________________________________ >>>Fra: Roger Hui <[email protected]> >>>Til: Programming forum <[email protected]> >>>Sendt: 18:07 lørdag den 29. oktober 2011 >>>Emne: Re: [Jprogramming] 32- & 64-bit PRNGs >>> >>>Ah yes, _1j1.22461e_16. I can't do much about the 1.22461e_16 >>>(welcome to the ugly realities of floating point arithmetic), but I >>>can do this: >>> >>> ^@o. j. 0.5 * i. 3 4 >>>1 0j1 _1 0j_1 >>>1 0j1 _1 0j_1 >>>1 0j1 _1 0j_1 >>> >>> ^@o. j. 2e9 + 0.5 * i. 3 4 >>>1 0j1 _1 0j_1 >>>1 0j1 _1 0j_1 >>>1 0j1 _1 0j_1 >>> >>>(In J7.01.) >>> >>> >>> >>>On Sat, Oct 29, 2011 at 8:48 AM, Linda Alvord <[email protected]> >>>wrote: >>>> Here's what I was thinking: >>>> >>>> >>>> -^1p1*0j1 >>>> 1j_1.22465e_16 >>>> >>>> I forgot that "i" is 0j1 (quite a coincidence?) in J >>>> >>>> Also, it was always more satisfying to me that the result is 1. >>>> >>>> However, we do agree. >>>> >>>> -^1p1*0j1 >>>> 1j_1.22465e_16 >>>> >>>> >>>> -----Original Message----- >>>> From: [email protected] >>>> [mailto:[email protected]] On Behalf Of Roger Hui >>>> Sent: Friday, October 28, 2011 11:48 AM >>>> To: Programming forum >>>> Subject: Re: [Jprogramming] 32- & 64-bit PRNGs >>>> >>>> Isn't that just saying that (^1)^0 is 1? On the other hand: >>>> >>>> _1 = ^ 1p1 * 0j1 >>>> 1 >>>> >>>> http://www.jsoftware.com/jwiki/Essays/Euler%27s%20Identity >>>> >>>> >>>> >>>> On Fri, Oct 28, 2011 at 12:48 AM, Linda Alvord <[email protected]> >>>> wrote: >>>>> Ken might have answered that God must be an awesome mathematician, since >>>>> he might have understood God better than most. >>>>> >>>>> (^1)^-o.i.1 >>>>> 1 >>>>> >>>>> >>>>> -----Original Message----- >>>>> From: [email protected] >>>>> [mailto:[email protected]] On Behalf Of Ian Clark >>>>> Sent: Thursday, October 27, 2011 2:38 PM >>>>> To: Programming forum >>>>> Subject: Re: [Jprogramming] 32- & 64-bit PRNGs >>>>> >>>>> I wonder if Carl Sagan, like Feynman, wasn't having joke after joke at >>>>> his audience's expense? (APWJ p 136, see also end of: >>>>> http://www.jsoftware.com/jwiki/Doc/Articles/Play151) >>>>> >>>>> The probability of any given finite pattern turning up in the first N >>>>> digits of a random sequence tends to 1 as N tends to infinity. The >>>>> aforementioned site estimates the odds for various values of N: >>>>> http://www.angio.net/pi/piquery#likely >>>>> >>>>> Sagan didn't say how many digits Ellie had to search (N) for her >>>>> (initially undefined) pattern. Was N sufficiently low to reject the >>>>> null hypothesis? The implication is: it wasn't. Nor is pi a random >>>>> series (it's pseudo-random). And when you're reading the Mind of God >>>>> -- does the null hypothesis have any cause to exist? -- viz is there >>>>> any merit in *guessing* the Mind of God? >>>>> >>>>> Nor is it the first time in the novel Ellie is the victim of illusion >>>>> (the alien deludes her he's her father... and yet she knows that). >>>>> >>>>> The whole novel is shot through with existential jokes, playing-off >>>>> science against sentiment. Once I spotted that I was ready to forgive >>>>> Sagan any amount of Slartibartfastian pseudo-engineering of pi. >>>>> >>>>> >>>>> On Thu, Oct 27, 2011 at 1:51 PM, Roger Hui <[email protected]> >>>>> wrote: >>>>>>> For initial experiments, there's already a site which stores the first >>>>>>> 200M digits of pi, for hobbyists wanting to do Carl Sagan >>>>>>> "Contact"-type research: >>>>>> >>>>>> When I first read that in "Contact" years ago it knocked down by >>>>>> several notches my respect for the novel. Even the Almighty doesn't >>>>>> have any choice about the digits of π, right? What's He/She going to >>>>>> do about the various power series, f'instance? >>>>>> >>>>>> >>>>>> >>>>>> On Thu, Oct 27, 2011 at 5:26 AM, Ian Clark <[email protected]> wrote: >>>>>>> Being old enough to have learned my electronics before the digital >>>>>>> age, I wonder if it isn't time to reconsider shot noise as a source of >>>>>>> random numbers. It has a forensic advantage in lottery draws, and >>>>>>> monte-carlo simulations of fraught political topics like climate >>>>>>> change, by taking the "pseudo" out of "pseudo-random". >>>>>>> >>>>>>> For years the UK gov ran a device called ERNIE >>>>>>> http://en.wikipedia.org/wiki/ERNIE#ERNIE >>>>>>> to pick premium bonds (a savings scheme where the interest payable was >>>>>>> put in a monthly draw). >>>>>>> >>>>>>> A device to generate binary digits from electronic noise would be so >>>>>>> simple it ought to be fitted as standard to today's desktop computers. >>>>>>> Failing that, if I had a serious need for true random numbers I'd >>>>>>> experiment with an open microphone line using Audacity to save the >>>>>>> number stream as a WAV. >>>>>>> >>>>>>> Need a reproducible number stream? With the amount of free storage >>>>>>> space in the "cloud" (I currently have access to around 2 GB and I >>>>>>> don't remember asking for it) why not just store it? I also have a 1TB >>>>>>> disk drive, mostly lying empty. >>>>>>> >>>>>>> For initial experiments, there's already a site which stores the first >>>>>>> 200M digits of pi, for hobbyists wanting to do Carl Sagan >>>>>>> "Contact"-type research: >>>>>>> http://www.angio.net/pi/piquery >>>>>>> Aside: ought the hunt for meaningful sequences in pi to be called >>>>>>> perimancy? :-) >>>>>>> >>>>>>> >>>>>>> >>>>>>> On Fri, Oct 14, 2011 at 8:30 PM, Zsbán Ambrus <[email protected]> >>>>>>> wrote: >>>>>>>> On Fri, Oct 14, 2011 at 2:33 PM, Zsbán Ambrus <[email protected]> >>>>>>>> wrote: >>>>>>>>> On Fri, Oct 14, 2011 at 1:08 PM, Ewart Shaw <[email protected]> >>>>>>>>> wrote: >>>>>>>>>> I want to generate pseudorandom sequences that are the same for 32- >>>>>>>>>> & 64-bit J. >>>>>>>>> >>>>>>>>> Have you tried the other random generators the (9!:43) foreign makes >>>>>>>>> available? I'd guess some of them are the same for 32 and 64 bit J. >>>>>>>> >>>>>>>> Hmm, from a quick test, it seems Roger is right: none of the built in >>>>>>>> generators give the same results on the 32-bit and 64-bit J. >>>>>>>> >>>>>>>> Let's use the random generation functions from GSL ( >>>>>>>> http://www.gnu.org/software/gsl/ ) then. This example implements >>>>>>>> roll, but not deal. >>>>>>>> >>>>>>>> >>>>>>>> $ cat rngwrap.c >>>>>>>> #include <gsl/gsl_rng.h> >>>>>>>> >>>>>>>> /* >>>>>>>> Allocate a new random generator of the Mersenne Twister algorithm >>>>>>>> and initialize it with the default seed. >>>>>>>> */ >>>>>>>> gsl_rng * >>>>>>>> wrap_newrng(void) { >>>>>>>> gsl_rng *g = gsl_rng_alloc(gsl_rng_mt19937); >>>>>>>> return g; >>>>>>>> } >>>>>>>> >>>>>>>> $ cat rngwrap.ijs >>>>>>>> NB. random generator functions from GSL >>>>>>>> rngobj=: <'./rngwrap.so wrap_newrng > x'15!:0$0 >>>>>>>> rollint=: './rngwrap.so gsl_rng_uniform_int > x *c x'15!:0 rngobj;] >>>>>>>> rollflo=: './rngwrap.so gsl_rng_uniform_pos > d *c'15!:0 (,<rngobj)"_ >>>>>>>> roll=: rollflo`rollint`[:@.*"0 :[: >>>>>>>> >>>>>>>> $ gcc -Wall -O -fpic -lm -lgslcblas -lgsl -shared -o rngwrap.so >>>>>>>> rngwrap.c >>>>>>>> $ jconsole rngwrap.ijs >>>>>>>> roll (10$1e4),5$0 >>>>>>>> 9997 1629 2826 9472 2316 4849 9574 7443 5400 7399 0.759944 0.658637 >>>>>>>> 0.315638 0.804403 0.519672 >>>>>> ---------------------------------------------------------------------- >>>>>> 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 >---------------------------------------------------------------------- >For information about J forums see http://www.jsoftware.com/forums.htm > > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
