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Re: [Pharo-users] [Article] Speeding up factorial computation by changing the order of multiplications

by Sven Van Caekenberghe

> On 24 May 2016, at 10:55, Thierry Goubier <thierry.goubier(a)gmail.com> wrote: > > Hi Sven. > > Using '((self + upper) / 2 ) truncated' seems to be a little bit faster than 'self + upper bitshift: -1'. Is it ? Even so, you probably agree that that calculation involving the bounds that are not large integers is totally irrelevant in the light of the heavy multiplications of large integers with thousands of digits, no ? That is why I also said that the recursion cost is (probably) acceptable. Anyway, if you want to freak out, go read the Fast Factorial Functions website mentioned at the end http://www.luschny.de/math/factorial/FastFactorialFunctions.htm It is totally humbling (for me anyway) > Thierry > > > > 2016-05-24 9:57 GMT+02:00 Sven Van Caekenberghe <sven(a)stfx.eu>: > I just published a short, introduction level article, > > Speeding up factorial computation by changing the order of multiplications. > > This is a story about a small, seemingly innocent code change that speeds up a very simple computation. It is pretty magical and serves as an example of how things are not always what they seem. > > https://medium.com/concerning-pharo/speeding-up-factorial-computation-by-ch… > > Enjoy, > > Sven > > -- > Sven Van Caekenberghe > Proudly supporting Pharo > http://pharo.org > http://association.pharo.org > http://consortium.pharo.org > > > > > >

May 24, 2016

Re: [Pharo-users] [Article] Speeding up factorial computation by changing the order of multiplications

by Sven Van Caekenberghe

> On 24 May 2016, at 10:21, Serge Stinckwich <serge.stinckwich(a)gmail.com> wrote: > > Very nice article Sven ! Thanks, but it is just intro level (which is important too, of course). > Can you contribute your code to the PolyMath project under the MIT > Licence (and maybe some tests) ? It is only one method. You can copy it over if you want. I am not 100% happy with the selector name #productTo: either. And there should probably be some error checking in a facade method before going into the loop, like self assert: upper isInteger. self assert: (self between: 1 and: upper). Have you seen the Fast Factorial Functions website mentioned at the end ? http://www.luschny.de/math/factorial/FastFactorialFunctions.htm If I see that, I can only be very humble about the implementation in the article (which was based on some very old Lisp code that I had lying around - I did not come up with this myself). Sven > Thank you. > > On Tue, May 24, 2016 at 8:57 AM, Sven Van Caekenberghe <sven(a)stfx.eu> wrote: >> I just published a short, introduction level article, >> >> Speeding up factorial computation by changing the order of multiplications. >> >> This is a story about a small, seemingly innocent code change that speeds up a very simple computation. It is pretty magical and serves as an example of how things are not always what they seem. >> >> https://medium.com/concerning-pharo/speeding-up-factorial-computation-by-ch… >> >> Enjoy, >> >> Sven >> >> -- >> Sven Van Caekenberghe >> Proudly supporting Pharo >> http://pharo.org >> http://association.pharo.org >> http://consortium.pharo.org >> >> >> >> >> > > > > -- > Serge Stinckwich > UCBN & UMI UMMISCO 209 (IRD/UPMC) > Every DSL ends up being Smalltalk > http://www.doesnotunderstand.org/ >

May 24, 2016

Re: [Pharo-users] [Article] Speeding up factorial computation by changing the order of multiplications

by Thierry Goubier

Hi Sven. Using '((self + upper) / 2 ) truncated' seems to be a little bit faster than 'self + upper bitshift: -1'. Thierry 2016-05-24 9:57 GMT+02:00 Sven Van Caekenberghe <sven(a)stfx.eu>: > I just published a short, introduction level article, > > Speeding up factorial computation by changing the order of multiplications. > > This is a story about a small, seemingly innocent code change that speeds > up a very simple computation. It is pretty magical and serves as an example > of how things are not always what they seem. > > > https://medium.com/concerning-pharo/speeding-up-factorial-computation-by-ch… > > Enjoy, > > Sven > > -- > Sven Van Caekenberghe > Proudly supporting Pharo > http://pharo.org > http://association.pharo.org > http://consortium.pharo.org > > > > > >

May 24, 2016

Re: [Pharo-users] [Article] Speeding up factorial computation by changing the order of multiplications

by Serge Stinckwich

Very nice article Sven ! Can you contribute your code to the PolyMath project under the MIT Licence (and maybe some tests) ? Thank you. On Tue, May 24, 2016 at 8:57 AM, Sven Van Caekenberghe <sven(a)stfx.eu> wrote: > I just published a short, introduction level article, > > Speeding up factorial computation by changing the order of multiplications. > > This is a story about a small, seemingly innocent code change that speeds up a very simple computation. It is pretty magical and serves as an example of how things are not always what they seem. > > https://medium.com/concerning-pharo/speeding-up-factorial-computation-by-ch… > > Enjoy, > > Sven > > -- > Sven Van Caekenberghe > Proudly supporting Pharo > http://pharo.org > http://association.pharo.org > http://consortium.pharo.org > > > > > -- Serge Stinckwich UCBN & UMI UMMISCO 209 (IRD/UPMC) Every DSL ends up being Smalltalk http://www.doesnotunderstand.org/

May 24, 2016

[Article] Speeding up factorial computation by changing the order of multiplications

by Sven Van Caekenberghe

I just published a short, introduction level article, Speeding up factorial computation by changing the order of multiplications. This is a story about a small, seemingly innocent code change that speeds up a very simple computation. It is pretty magical and serves as an example of how things are not always what they seem. https://medium.com/concerning-pharo/speeding-up-factorial-computation-by-ch… Enjoy, Sven -- Sven Van Caekenberghe Proudly supporting Pharo http://pharo.org http://association.pharo.org http://consortium.pharo.org

May 24, 2016

Re: [Pharo-users] New Success Story: Sysmocom: Free Software for Mobile Communication

by Holger Freyther

> On 23 May 2016, at 22:28, Esteban A. Maringolo <emaringolo(a)gmail.com> wrote: > > It is really cool and impressive. > > Is any of the supporting libraries open-source? (like ASN.1) http://smalltalkhub.com/#!/~NorbertHartl/ASN1 The model/ASN1 parser is probably one of the most complete FOSS parser, the library is tied to DER/BER right now and it would be nice if someone adds *PER/JSON/XML encoding/decoding. holger

May 23, 2016

Re: [Pharo-users] New Success Story: Sysmocom: Free Software for Mobile Communication

by Esteban A. Maringolo

It is really cool and impressive. Is any of the supporting libraries open-source? (like ASN.1) Regards! Esteban A. Maringolo 2016-05-23 11:20 GMT-03:00 Mariano Martinez Peck <marianopeck(a)gmail.com>: > Wow, that is pretty nice! Nice to see another success story and we hope > there are more to come. > > Best, > > On Sun, May 22, 2016 at 8:05 AM, Marcus Denker <marcus.denker(a)inria.fr> > wrote: > >> Sysmocom: Free Software for Mobile Communication >> http://pharo.org/success/Sysmocom >> >> >> "Sysmocom is a leading provider of Free Software Mobile Communication >> solutions. In 2012 we have started a long term project to develop a >> complete ASN1, TCAP, MAP, CAP, GSN stack using the Pharo Object >> Environment. We have decided to use Pharo because of the increased >> productivity, the great tooling, the live inspection and if necessary >> modification of a running system to deploy a critical bugfix. Pharo has >> allowed us to focus on what is important. >> >> The stack was used to uncover security and privacy issues inherent to the >> MAP protocol design in 2014/2015. We have used the stack to build a >> carrier-grade AuthenticationCenter (AuC) and helped a customer to move >> their production traffic off a proprietary system to ours. We look forward >> to move a HomeLocationRegister (HLR) into production this year. said Holger >> Freyther CEO." >> >> >> >> >> > > > -- > Mariano > http://marianopeck.wordpress.com >

May 23, 2016

Re: [Pharo-users] OT - an opinion on node.js

by Bob Clark

On 05/23/2016 02:09 PM, Jimmie Houchin wrote: > > > On 05/23/2016 01:05 PM, Bob Clark wrote: >> >> On 05/23/2016 09:50 AM, Ben Coman wrote: >>> On Mon, May 23, 2016 at 4:44 PM, Peter UhnÃ¡k <i.uhnak(a)gmail.com> wrote: >>>> The video is intentionally inflammatory and I don't really see a >>>> reason why >>>> we would need to either start a flame war (if there are node.js >>>> devs reading >>>> it), or an echo chamber (so we all just put ourselves on the back >>>> hour great >>>> our Pharo is). >>>> >>>>> Never used it. >>>>> I'd be interested to hear any counter opinons. >>>> wtf? >>> you a right. I'm embarrassed I didn't think it through. >>> I apologise, it was out of line. >>> -ben >> >> Thanks for posting this, I got to really laughing and my morning is >> much better now. I didn't quite hear what he said, I thought I heard >> LIPS? Did he say It's because of you ... we are all using LIPS? Is >> that slang for Pharo? Does Pharo have some project named LIPS? I am a >> little confused. What is it? >> > > I don't know if you are serious or are being funny. Either way he > said, LISP. > https://en.wikipedia.org/wiki/Lisp_(programming_language) > > An older and interesting language. > > Jimmie > Well, yes, :) I wass trying to be funny but also to link to pharo. I think lisp co-evolved with smalltalk-80 yes, so there's a connection. Lets think about what LiPS could be in pharo... I thinkits the Little Presentation System, a minimal & modular UI/Ux than can be loaded into a headless image, and expanded as needed. Then when a headless instance gets hurt, we'd add some Lips to make it better. We have a better mythology. > > An older and interesting language. very. bob

May 23, 2016

Re: [Pharo-users] OT - an opinion on node.js

by Dimitris Chloupis

I think from what I have heard at least people use Node.js because its well designed and because they can use a language many people are familiar with Javascript. Personally I have little interest in web development . I cant say I find the video funny since it seems to draw a caricature over people who prefer one technology over another. Afterall you could as well make a video about Pharo vs other languages and IDEs and debate that the boosted productivity is not much and in cases much slower than using other languages. The answer to those matters is never simple anyway. And In the end what it counts is the end results, all those tools are just means to an end. So try to convince people about which is best, is kinda pointless as it is this video. We can all be friendly make our own choices without offending other people. On Mon, May 23, 2016 at 8:43 PM Jimmie Houchin <jlhouchin(a)gmail.com> wrote: > Personally, I don't think it is out of line. Off topic, as you stated, > but not out of line. > > Here is the deal. The people on this mailing list form a community. We > get to know each other in a manner. We trust and value the opinions of > at least some of the people in this community. To me it is okay to ask > off topic question and opinions within limits. If that were the only > contribution to the community. The person might be more like a troll. > You my friend are no troll. You are a regular and valued member of the > community and deserve some liberty for off topic conversation. :) > > Just one community member's opinion. > > No opinion on the video (haven't watched it yet) nor node.js (never used > it). > > Jimmie > > > On 05/23/2016 08:50 AM, Ben Coman wrote: > > On Mon, May 23, 2016 at 4:44 PM, Peter UhnÃ¡k <i.uhnak(a)gmail.com> wrote: > >> The video is intentionally inflammatory and I don't really see a reason > why > >> we would need to either start a flame war (if there are node.js devs > reading > >> it), or an echo chamber (so we all just put ourselves on the back hour > great > >> our Pharo is). > >> > >>> Never used it. > >>> I'd be interested to hear any counter opinons. > >> wtf? > > you a right. I'm embarrassed I didn't think it through. > > I apologise, it was out of line. > > -ben > > > > >

May 23, 2016

Re: [Pharo-users] OT - an opinion on node.js

by Jimmie Houchin

On 05/23/2016 01:05 PM, Bob Clark wrote: > > On 05/23/2016 09:50 AM, Ben Coman wrote: >> On Mon, May 23, 2016 at 4:44 PM, Peter UhnÃ¡k <i.uhnak(a)gmail.com> wrote: >>> The video is intentionally inflammatory and I don't really see a >>> reason why >>> we would need to either start a flame war (if there are node.js devs >>> reading >>> it), or an echo chamber (so we all just put ourselves on the back >>> hour great >>> our Pharo is). >>> >>>> Never used it. >>>> I'd be interested to hear any counter opinons. >>> wtf? >> you a right. I'm embarrassed I didn't think it through. >> I apologise, it was out of line. >> -ben > > Thanks for posting this, I got to really laughing and my morning is > much better now. I didn't quite hear what he said, I thought I heard > LIPS? Did he say It's because of you ... we are all using LIPS? Is > that slang for Pharo? Does Pharo have some project named LIPS? I am a > little confused. What is it? > I don't know if you are serious or are being funny. Either way he said, LISP. https://en.wikipedia.org/wiki/Lisp_(programming_language) An older and interesting language. Jimmie

May 23, 2016