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Help with bit bashing code: differences between C and CL
by Marco Antoniotti 12 Nov '23

12 Nov '23

Dear all, I am hitting a wall with the attached code in CL and C versions. For those interested, this is code lifted from Knuth's pages on random number generation (https://www-cs-faculty.stanford.edu/~knuth/programs.html#rng) The problem is that there is a discrepancy in the "problem" loop between the CL and the C and I cannot figure out why, although the culprit may be that CL does not have "proper" 64 bits ints. I am running on LW 8.x on an Intel Mac. I have not tried on other CL implementations/platforms. I compile the C code with clang (Apple clang version 15.0.0 (clang-1500.0.40.1) If you run the code, you will see that the discrepancy appears at 'j = 14' in the loop. What gives? Thanks Marco -- Marco Antoniotti, Professor tel. +39 - 02 64 48 79 01 DISCo, Università Milano Bicocca U14 2043 http://dcb.disco.unimib.it Viale Sarca 336 I-20126 Milan (MI) ITALY

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Re: Help with bit bashing code: differences between C and CL
by Marco Antoniotti 10 Nov '23

10 Nov '23

Thank you. I have not checked the details, but are you implying that clang printf is... buggy? Knuth has such a caveat (about buggy printf implementations) on his page. All the best Marco On Fri, Nov 10, 2023 at 11:35 AM <raymond.wiker(a)icloud.com> wrote: > I think that clang is simply printing more information than it is allowed > (or supposed) to. For a double-precision IEEE754 float, the number of > significant digits should be > > (floor (* 54.0d0 (/ (log 2.0d0) (log 10.0d0)))) > > which evaluates to 16 (53-bit mantissa + 1 hidden digit). The Lisp output > has exactly 16 significant digits, while the clang output has 20. > > The actual correct digits seem to be > > (ash (expt 10 52) -52) > > which evaluates to > > 2220446049250313080847263336181640625. > > > > > > On 10 Nov 2023, at 09:55, Marco Antoniotti (as marco dot antoniotti at > unimib dot it) <lisp-hug(a)lispworks.com> wrote: > > Hi > > Thanks Pascal. > > For LW on Intel (Mac) the ULP seems the same. With SBCL you should > actually be able to peek at the actual bits making up the double float. > Can you do something similar with LM? > > Just curious: has anybody tried this on a M*/Arm Mac? Or, with LW, on > your smartphone? :) > > Cheers > > MA > > > On Fri, Nov 10, 2023 at 8:29 AM Pascal Bourguignon (as pjb at > informatimago dot com) <lisp-hug(a)lispworks.com> wrote: > >> >> >> On 9 Nov 2023, at 21:21, Marco Antoniotti <marco.antoniotti(a)unimib.it> >> wrote: >> >> <problem-loop.lisp> >> >> >> >> From the start, it looks like the ulp is more precise in C: >> >> >> sbcl: 2.220446049250313d-16 >> clang: 2.2204460492503130808e-16 >> >> (using %.20g instead of %.20f) >> >> Or perhaps it’s only the display procedure that truncates in lisp? >> >> -- >> __Pascal J. Bourguignon__ >> >> >> >> >> >

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Re: Help with bit bashing code: differences between C and CL
by Marco Antoniotti 09 Nov '23

09 Nov '23

Thanks. This is weird. The C and Fortran versions seem to agree. Marco On Thu, Nov 9, 2023 at 9:49 PM Frank Gönninger | Gönninger B&T < frank.goenninger(a)goenninger.net> wrote: > Hi Marco, > > > > on AllegroCL 11.0 beta Enterprise Edition I get diverging results starting > at j = 21… > > > > Lisp: j = 21; ss = 0.00028959847986698150 > > C: j = 21; ss = 0.00028959847986698151 > > > > FWIW … > > > > Best, > > Frank > > > > *Von: *<owner-lisp-hug(a)lispworks.com> im Auftrag von "Marco Antoniotti > (as marco dot antoniotti at unimib dot it)" <lisp-hug(a)lispworks.com> > *Antworten an: *Marco Antoniotti <marco.antoniotti(a)unimib.it> > *Datum: *Donnerstag, 9. November 2023 um 21:23 > *An: *LispWorks <lisp-hug(a)lispworks.com>, Discussion list for Common Lisp > professionals <pro(a)common-lisp.net> > *Betreff: *Help with bit bashing code: differences between C and CL > > > > Dear all, > > > > I am hitting a wall with the attached code in CL and C versions. For > those interested, this is code lifted from Knuth's pages on random number > generation (https://www-cs-faculty.stanford.edu/~knuth/programs.html#rng) > > The problem is that there is a discrepancy in the "problem" loop between > the CL and the C and I cannot figure out why, although the culprit may be > that CL does not have "proper" 64 bits ints. > > I am running on LW 8.x on an Intel Mac. I have not tried on other CL > implementations/platforms. I compile the C code with clang (Apple clang > version 15.0.0 (clang-1500.0.40.1) > > > > If you run the code, you will see that the discrepancy appears at 'j = 14' > in the loop. > > > > What gives? > > Thanks > > Marco > > > > > > > -- > > Marco Antoniotti, Professor tel. +39 - 02 64 48 79 01 > DISCo, Università Milano Bicocca U14 2043 http://dcb.disco.unimib.it > Viale Sarca 336 > I-20126 Milan (MI) ITALY >

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Re: Common Lisp Transformer Libraries
by Marco Antoniotti 14 Aug '23

14 Aug '23

Hi Burton no. I have not heard of anything similar, except maybe from Mark Watson (who should be on these lists - markwatson.com) I became interested in them as well. In any case, the issue is whether you are interested in a CL implementation or a binding to this or that C/C++ library (yeah! I refrain from mentioning languages susceptible to the 'irsabol attack' 😑 ). All the best Marco On Sat, Aug 12, 2023 at 2:38 AM Burton John Samograd (as burtonjohnsamograd at protonmail dot com) <lisp-hug(a)lispworks.com> wrote: > Hello, > > I was wondering if anybody on this list (or anybody you might know) has > heard or had experience with a Common Lisp "Transformer" library, as in > Transformer from Generalized Pre-trained Transformer (GPT). > > I'd like to do some experimentation and was wondering if there was any > previous work that has been done that can be used. > > -- > Burton John Samograd > burtonjohnsamograd(a)protonmail.com > http://burton.samograd.ca/ > 2023 > > Sent with Proton Mail <https://proton.me/> secure email. > > ------- Forwarded Message ------- > From: Burton John Samograd <burtonjohnsamograd(a)protonmail.com> > Date: On Friday, August 11th, 2023 at 5:33 PM > Subject: Common Lisp Transformer Libraries > To: pro(a)common-lisp.net <pro(a)common-lisp.net> > > Hello, > > I was wondering if anybody on this list (or anybody you might know) has > heard or had experience with a Common Lisp "Transformer" library, as in > Transformer from Generalized Pre-trained Transformer (GPT). > > I'd like to do some experimentation and was wondering if there was any > previous work that has been done that can be used. > > Thank you. > > -- > Burton John Samograd > burtonjohnsamograd(a)protonmail.com > 2023 > > Sent with Proton Mail <https://proton.me/> secure email. > > >

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Common Lisp Transformer Libraries
by Burton John Samograd 11 Aug '23

11 Aug '23

Hello, I was wondering if anybody on this list (or anybody you might know) has heard or had experience with a Common Lisp "Transformer" library, as in Transformer from Generalized Pre-trained Transformer (GPT). I'd like to do some experimentation and was wondering if there was any previous work that has been done that can be used. Thank you. -- Burton John Samograd burtonjohnsamograd(a)protonmail.com 2023 Sent with [Proton Mail](https://proton.me/) secure email.

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simple URL GET
by paul tarvydas 08 May '23

08 May '23

I want to GET a URL and put the result into a string with as little fuss as possible, but nothing seems to work. I am trying to follow: https://lispcookbook.github.io/cl-cookbook/web-scraping.html using SBCL and LispWorks. I'm on a MacBook (Ventura) and am getting SSL errors (plus unicode errors in Lispworks). Reminders as to how to fix such problems would be appreciated... thanks pt

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Fwd: domain clos.org
by Dave Cooper 03 May '23

03 May '23

---------- Forwarded message --------- From: Dave Cooper <david.cooper(a)genworks.com> Date: Wed, May 3, 2023, 05:08 Subject: Re: domain clos.org To: Erik Huelsmann <ehuels(a)gmail.com> Cc: CL Foundation <clf(a)cl-foundation.org> I'm pretty sure the Common Lisp Foundation can take this on. We have our other domains (e.g. common-lisp.net, common-lisp.dev) with Gandi with an organizational account. On Tue, May 2, 2023, 17:59 Erik Huelsmann <ehuels(a)gmail.com> wrote: > > ---------- Forwarded message --------- > From: Kevin Layer <layer(a)franz.com> > Date: Tue, May 2, 2023, 21:10 > Subject: domain clos.org > To: <pro(a)common-lisp.net> > > > Hi, everyone. We have this domain. Does anyone want it? > This is not a first come, first served thing, so just shoot me an > email and I'll give it to a worthy person/cause. > > -- > Kevin Layer > Franz Inc. > > -- > To unsubscribe from this group and stop receiving emails from it, send an > email to clf+unsubscribe(a)cl-foundation.org. >

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domain clos.org
by Kevin Layer 02 May '23

02 May '23

Hi, everyone. We have this domain. Does anyone want it? This is not a first come, first served thing, so just shoot me an email and I'll give it to a worthy person/cause. -- Kevin Layer Franz Inc.

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Password input in a console application
by Alessio Stalla 21 Apr '23

21 Apr '23

Greetings everyone, is there a well-known way to do the thing in the subject, i.e. ask the user for a password in a console application, reading from the keyboard without echoing anything to the terminal? Using a library is fine, SBCL only is fine, limited to some OS is not so fine but better than nothing. Any idea?

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Numpy and Common Lisp?
by Robert Goldman 13 Apr '23

13 Apr '23

Has anyone taken the Numpy C API and created a CFFI library based on it? I see some attempts to clone it in pure CL, but I would guess that just using it through its API might be easier and more effective.

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