July 2014 - Pharo-dev - lists.pharo.org

Re: [Pharo-dev] Division isn't correct

by Andres Valloud

I don't think it makes sense to compare floating point numbers to other types of numbers with #=... there's a world of approximations and other factors hiding behind #=, and the occasional true answer confuses more than it helps. On top of that, then you get x = y => x hash = y hash, and so the hash of floating point values "has" to be synchronized with integers, fractions, scaled decimals, etc... _what a mess_... On 7/11/14 10:46 , stepharo wrote: > I suggest you to read the Small number chapter of the Deep into Pharo. > > Stef > > On 11/7/14 15:53, Natalia Tymchuk wrote: >> Hello. >> I found interesting thing: >> Why it is like this? >> >> Best regards, >> Natalia >> >

July 11, 2014

Re: [Pharo-dev] Doc of mustache

by Damien Cassou

Le 11 juil. 2014 10:50, "stepharo" <stepharo(a)free.fr> a Ã©crit : > > I would like to see if there is an XHTML outputer that takes it into account. > I will check pillar. Pillar uses mustache

July 11, 2014

Re: [Pharo-dev] DBXTalk > OpenDBX > MySQL and OSX Lion : working on 2.0

by Dokania, Harshit

Thanks for your reply. I was not sure where to use "-g" option, I tried using ./odbxtest -g -b mysql -h localhost -p 3306 -d sodbxtest -u sodbxtest -w sodbxtest. But that didn't work. Harshit ________________________________________ From: Pharo-dev [pharo-dev-bounces(a)lists.pharo.org] on behalf of phil(a)highoctane.be [phil(a)highoctane.be] Sent: Friday, July 11, 2014 12:19 PM To: Pharo Development List Subject: Re: [Pharo-dev] DBXTalk > OpenDBX > MySQL and OSX Lion : working on 2.0 It complied on Lion with thr config above. Now if you could do a build with -g and look at why you segfault with gdb we could tell more. Phil On Friday, July 11, 2014, Dokania, Harshit <hdokani2(a)illinois.edu<mailto:hdokani2@illinois.edu>> wrote: Hello, It will be really helpful if someone can comment on that, as I am not able to proceed. Thanks, Harshit ________________________________________ From: Pharo-dev [pharo-dev-bounces(a)lists.pharo.org] on behalf of harshit [hdokani2(a)illinois.edu] Sent: Thursday, July 10, 2014 7:37 PM To: pharo-dev(a)lists.pharo.org Subject: Re: [Pharo-dev] DBXTalk > OpenDBX > MySQL and OSX Lion : working on 2.0 Hello Following Phil's post I could get it working till here. mysql -usodbxtest -psodbxtest sodbxtest When I enter ./odbxtest -b mysql -h localhost -p 3306 -d sodbxtest -u sodbxtest -w sodbxtest from stable-1.4/test I get following ODBX_CAP_BASIC: 1 ODBX_CAP_LO: 0 ODBX_OPT_API_VERSION: 10200 ODBX_OPT_THREAD_SAFE: 1 ODBX_OPT_TLS: 1 ODBX_OPT_CONNECT_TIMEOUT: 1 (using) ODBX_OPT_MULTI_STATEMENTS: 1 (using) ODBX_OPT_PAGED_RESULTS: 1 (using) ODBX_OPT_COMPRESS: 1 (using) ODBX_CAP_BASIC: 1 ODBX_CAP_LO: 0 ODBX_OPT_API_VERSION: 10200 ODBX_OPT_THREAD_SAFE: 1 ODBX_OPT_TLS: 1 ODBX_OPT_CONNECT_TIMEOUT: 1 (using) ODBX_OPT_MULTI_STATEMENTS: 1 (using) ODBX_OPT_PAGED_RESULTS: 1 (using) ODBX_OPT_COMPRESS: 1 (using) Segmentation fault: 11 Any ideas what am I missing. Thanks, Harshit -- View this message in context: http://forum.world.st/Pharo-dev-DBXTalk-OpenDBX-MySQL-and-OSX-Lion-working-… Sent from the Pharo Smalltalk Developers mailing list archive at Nabble.com. -- --- Philippe Back Visible Performance Improvements Mob: +32(0) 478 650 140 | Fax: +32 (0) 70 408 027 Mail:phil@highoctane.be<mailto:Mail%3Aphil@highoctane.be> | Web: http://philippeback.eu Blog: http://philippeback.be | Twitter: @philippeback Youtube: http://www.youtube.com/user/philippeback/videos High Octane SPRL rue cour Boisacq 101 | 1301 Bierges | Belgium Pharo Consortium Member - http://consortium.pharo.org/ Featured on the Software Process and Measurement Cast - http://spamcast.libsyn.com Sparx Systems Enterprise Architect and Ability Engineering EADocX Value Added Reseller

July 11, 2014

Re: [Pharo-dev] DBXTalk > OpenDBX > MySQL and OSX Lion : working on 2.0

by phil＠highoctane.be

It complied on Lion with thr config above. Now if you could do a build with -g and look at why you segfault with gdb we could tell more. Phil On Friday, July 11, 2014, Dokania, Harshit <hdokani2(a)illinois.edu> wrote: > Hello, > > It will be really helpful if someone can comment on that, as I am not able > to proceed. > > Thanks, > Harshit > ________________________________________ > From: Pharo-dev [pharo-dev-bounces(a)lists.pharo.org <javascript:;>] on > behalf of harshit [hdokani2(a)illinois.edu <javascript:;>] > Sent: Thursday, July 10, 2014 7:37 PM > To: pharo-dev(a)lists.pharo.org <javascript:;> > Subject: Re: [Pharo-dev] DBXTalk > OpenDBX > MySQL and OSX Lion : working > on 2.0 > > Hello > > Following Phil's post I could get it working till here. mysql -usodbxtest > -psodbxtest sodbxtest > > When I enter ./odbxtest -b mysql -h localhost -p 3306 -d sodbxtest -u > sodbxtest -w sodbxtest from stable-1.4/test > I get following > ODBX_CAP_BASIC: 1 > ODBX_CAP_LO: 0 > ODBX_OPT_API_VERSION: 10200 > ODBX_OPT_THREAD_SAFE: 1 > ODBX_OPT_TLS: 1 > ODBX_OPT_CONNECT_TIMEOUT: 1 (using) > ODBX_OPT_MULTI_STATEMENTS: 1 (using) > ODBX_OPT_PAGED_RESULTS: 1 (using) > ODBX_OPT_COMPRESS: 1 (using) > ODBX_CAP_BASIC: 1 > ODBX_CAP_LO: 0 > ODBX_OPT_API_VERSION: 10200 > ODBX_OPT_THREAD_SAFE: 1 > ODBX_OPT_TLS: 1 > ODBX_OPT_CONNECT_TIMEOUT: 1 (using) > ODBX_OPT_MULTI_STATEMENTS: 1 (using) > ODBX_OPT_PAGED_RESULTS: 1 (using) > ODBX_OPT_COMPRESS: 1 (using) > Segmentation fault: 11 > > Any ideas what am I missing. > > Thanks, > Harshit > > > > > -- > View this message in context: > http://forum.world.st/Pharo-dev-DBXTalk-OpenDBX-MySQL-and-OSX-Lion-working-… > Sent from the Pharo Smalltalk Developers mailing list archive at > Nabble.com. > > -- --- Philippe Back Visible Performance Improvements Mob: +32(0) 478 650 140 | Fax: +32 (0) 70 408 027 Mail:phil@highoctane.be | Web: http://philippeback.eu Blog: http://philippeback.be | Twitter: @philippeback Youtube: http://www.youtube.com/user/philippeback/videos High Octane SPRL rue cour Boisacq 101 | 1301 Bierges | Belgium Pharo Consortium Member - http://consortium.pharo.org/ Featured on the Software Process and Measurement Cast - http://spamcast.libsyn.com Sparx Systems Enterprise Architect and Ability Engineering EADocX Value Added Reseller

July 11, 2014

Re: [Pharo-dev] DBXTalk > OpenDBX > MySQL and OSX Lion : working on 2.0

by Dokania, Harshit

Hello, It will be really helpful if someone can comment on that, as I am not able to proceed. Thanks, Harshit ________________________________________ From: Pharo-dev [pharo-dev-bounces(a)lists.pharo.org] on behalf of harshit [hdokani2(a)illinois.edu] Sent: Thursday, July 10, 2014 7:37 PM To: pharo-dev(a)lists.pharo.org Subject: Re: [Pharo-dev] DBXTalk > OpenDBX > MySQL and OSX Lion : working on 2.0 Hello Following Phil's post I could get it working till here. mysql -usodbxtest -psodbxtest sodbxtest When I enter ./odbxtest -b mysql -h localhost -p 3306 -d sodbxtest -u sodbxtest -w sodbxtest from stable-1.4/test I get following ODBX_CAP_BASIC: 1 ODBX_CAP_LO: 0 ODBX_OPT_API_VERSION: 10200 ODBX_OPT_THREAD_SAFE: 1 ODBX_OPT_TLS: 1 ODBX_OPT_CONNECT_TIMEOUT: 1 (using) ODBX_OPT_MULTI_STATEMENTS: 1 (using) ODBX_OPT_PAGED_RESULTS: 1 (using) ODBX_OPT_COMPRESS: 1 (using) ODBX_CAP_BASIC: 1 ODBX_CAP_LO: 0 ODBX_OPT_API_VERSION: 10200 ODBX_OPT_THREAD_SAFE: 1 ODBX_OPT_TLS: 1 ODBX_OPT_CONNECT_TIMEOUT: 1 (using) ODBX_OPT_MULTI_STATEMENTS: 1 (using) ODBX_OPT_PAGED_RESULTS: 1 (using) ODBX_OPT_COMPRESS: 1 (using) Segmentation fault: 11 Any ideas what am I missing. Thanks, Harshit -- View this message in context: http://forum.world.st/Pharo-dev-DBXTalk-OpenDBX-MySQL-and-OSX-Lion-working-… Sent from the Pharo Smalltalk Developers mailing list archive at Nabble.com.

July 11, 2014

Re: [Pharo-dev] Division isn't correct

by stepharo

I suggest you to read the Small number chapter of the Deep into Pharo. Stef On 11/7/14 15:53, Natalia Tymchuk wrote: > Hello. > I found interesting thing: > Why it is like this? > > Best regards, > Natalia >

July 11, 2014

Re: [Pharo-dev] Division isn't correct

by Nicolas Cellier

2014-07-11 17:14 GMT+02:00 Camille Teruel <camille.teruel(a)gmail.com>: > > On 11 juil. 2014, at 17:02, Natalia Tymchuk <natalia.tymchuk(a)unikernel.net> > wrote: > > But why > 185/10 = 18.5 -> true? > > > Because 18.5 has an exact float representation, while 0.2 hasn't. > > Couldn't we use #asApproximateFraction instead of #asTrueFraction in > Float>>adaptToFraction:andCompare: ? > No, it would be a bad thing. For example, it would break the fact that = should be an equivalence relation (a=b && (b=c) ==> (a=c)). See for example http://bugs.squeak.org/view.php?id=3374 for a genesis of this feature. And note that lispers have preceded us by many years. > 0.2 asApproximateFraction ==> (1/5) > 0.2 asTrueFraction ==> (3602879701896397/18014398509481984) > > > There is also asMinimalDecimalFraction or something like that. > > On Jul 11, 2014, at 4:40 PM, Norbert Hartl <norbert(a)hartl.name> wrote: > > > Am 11.07.2014 um 16:33 schrieb Yuriy Tymchuk <yuriy.tymchuk(a)me.com>: > > > On 11 Jul 2014, at 16:30, Esteban Lorenzano <estebanlm(a)gmail.com> wrote: > > On 11 Jul 2014, at 16:22, kilon alios <kilon.alios(a)gmail.com> wrote: > > why not round it before comparing it ? looks like an easy enough problem > to fix . I would expect that to be equal. > > > because it wouldnât be correct :) > > > But then why 4/2 = 2? > > > The same reason why > > 4/3 = 8/6 > > :) > > Norbert > > > > > > On Fri, Jul 11, 2014 at 5:18 PM, Yuriy Tymchuk <yuriy.tymchuk(a)me.com> > wrote: > >> Thatâs why mathematics and programming are two different thingsâ¦ >> >> >> On 11 Jul 2014, at 16:08, Esteban A. Maringolo <emaringolo(a)gmail.com> >> wrote: >> >> > Usually comparing against floats is not as deterministic as you would >> > expect. And in other dialects you use #equals: instead of #= >> > >> > But in Pharo there is no #equals: and instead there is a #closeTo:, >> > but #closeTo: has an arbitrary decimal precision, more than enough for >> > commong arithmetic. >> > >> > Regards! >> > >> > Esteban A. Maringolo >> > >> > >> > 2014-07-11 10:59 GMT-03:00 Goubier Thierry <thierry.goubier(a)cea.fr>: >> >> :) >> >> >> >> in Smalltalk, the division of two integers is a fraction, not a float. >> >> >> >> i.e. 1/5 is 1/5. >> >> >> >> Thierry >> >> >> >> Le 11/07/2014 15:53, Natalia Tymchuk a Ã©crit : >> >>> >> >>> Hello. >> >>> I found interesting thing: >> >>> Why it is like this? >> >>> >> >>> Best regards, >> >>> Natalia >> >>> >> >> >> >> -- >> >> Thierry Goubier >> >> CEA list >> >> Laboratoire des Fondations des SystÃ¨mes Temps RÃ©el EmbarquÃ©s >> >> 91191 Gif sur Yvette Cedex >> >> France >> >> Phone/Fax: +33 (0) 1 69 08 32 92 / 83 95 >> >> >> > >> >> >> > > > > > >

July 11, 2014

Re: [Pharo-dev] Division isn't correct

by Natalia Tymchuk

Thanks all of you. Best regards, Natalia On Jul 11, 2014, at 5:14 PM, Camille Teruel <camille.teruel(a)gmail.com> wrote: > > On 11 juil. 2014, at 17:02, Natalia Tymchuk <natalia.tymchuk(a)unikernel.net> wrote: > >> But why >> 185/10 = 18.5 -> true? > > Because 18.5 has an exact float representation, while 0.2 hasn't. > > Couldn't we use #asApproximateFraction instead of #asTrueFraction in Float>>adaptToFraction:andCompare: ? > 0.2 asApproximateFraction ==> (1/5) > 0.2 asTrueFraction ==> (3602879701896397/18014398509481984) > > >> >> On Jul 11, 2014, at 4:40 PM, Norbert Hartl <norbert(a)hartl.name> wrote: >> >>> >>> Am 11.07.2014 um 16:33 schrieb Yuriy Tymchuk <yuriy.tymchuk(a)me.com>: >>> >>>> >>>> On 11 Jul 2014, at 16:30, Esteban Lorenzano <estebanlm(a)gmail.com> wrote: >>>> >>>>> On 11 Jul 2014, at 16:22, kilon alios <kilon.alios(a)gmail.com> wrote: >>>>> >>>>>> why not round it before comparing it ? looks like an easy enough problem to fix . I would expect that to be equal. >>>>> >>>>> because it wouldnât be correct :) >>>> >>>> But then why 4/2 = 2? >>> >>> The same reason why >>> >>> 4/3 = 8/6 >>> >>> :) >>> >>> Norbert >>>> >>>>> >>>>>> >>>>>> >>>>>> On Fri, Jul 11, 2014 at 5:18 PM, Yuriy Tymchuk <yuriy.tymchuk(a)me.com> wrote: >>>>>> Thatâs why mathematics and programming are two different thingsâ¦ >>>>>> >>>>>> >>>>>> On 11 Jul 2014, at 16:08, Esteban A. Maringolo <emaringolo(a)gmail.com> wrote: >>>>>> >>>>>> > Usually comparing against floats is not as deterministic as you would >>>>>> > expect. And in other dialects you use #equals: instead of #= >>>>>> > >>>>>> > But in Pharo there is no #equals: and instead there is a #closeTo:, >>>>>> > but #closeTo: has an arbitrary decimal precision, more than enough for >>>>>> > commong arithmetic. >>>>>> > >>>>>> > Regards! >>>>>> > >>>>>> > Esteban A. Maringolo >>>>>> > >>>>>> > >>>>>> > 2014-07-11 10:59 GMT-03:00 Goubier Thierry <thierry.goubier(a)cea.fr>: >>>>>> >> :) >>>>>> >> >>>>>> >> in Smalltalk, the division of two integers is a fraction, not a float. >>>>>> >> >>>>>> >> i.e. 1/5 is 1/5. >>>>>> >> >>>>>> >> Thierry >>>>>> >> >>>>>> >> Le 11/07/2014 15:53, Natalia Tymchuk a Ã©crit : >>>>>> >>> >>>>>> >>> Hello. >>>>>> >>> I found interesting thing: >>>>>> >>> Why it is like this? >>>>>> >>> >>>>>> >>> Best regards, >>>>>> >>> Natalia >>>>>> >>> >>>>>> >> >>>>>> >> -- >>>>>> >> Thierry Goubier >>>>>> >> CEA list >>>>>> >> Laboratoire des Fondations des SystÃ¨mes Temps RÃ©el EmbarquÃ©s >>>>>> >> 91191 Gif sur Yvette Cedex >>>>>> >> France >>>>>> >> Phone/Fax: +33 (0) 1 69 08 32 92 / 83 95 >>>>>> >> >>>>>> > >>>>>> >>>>>> >>>>>> >>>>> >>>> >>> >> >

July 11, 2014

Re: [Pharo-dev] Division isn't correct

by Camille Teruel

On 11 juil. 2014, at 17:02, Natalia Tymchuk <natalia.tymchuk(a)unikernel.net> wrote: > But why > 185/10 = 18.5 -> true? Because 18.5 has an exact float representation, while 0.2 hasn't. Couldn't we use #asApproximateFraction instead of #asTrueFraction in Float>>adaptToFraction:andCompare: ? 0.2 asApproximateFraction ==> (1/5) 0.2 asTrueFraction ==> (3602879701896397/18014398509481984) > > On Jul 11, 2014, at 4:40 PM, Norbert Hartl <norbert(a)hartl.name> wrote: > >> >> Am 11.07.2014 um 16:33 schrieb Yuriy Tymchuk <yuriy.tymchuk(a)me.com>: >> >>> >>> On 11 Jul 2014, at 16:30, Esteban Lorenzano <estebanlm(a)gmail.com> wrote: >>> >>>> On 11 Jul 2014, at 16:22, kilon alios <kilon.alios(a)gmail.com> wrote: >>>> >>>>> why not round it before comparing it ? looks like an easy enough problem to fix . I would expect that to be equal. >>>> >>>> because it wouldnât be correct :) >>> >>> But then why 4/2 = 2? >> >> The same reason why >> >> 4/3 = 8/6 >> >> :) >> >> Norbert >>> >>>> >>>>> >>>>> >>>>> On Fri, Jul 11, 2014 at 5:18 PM, Yuriy Tymchuk <yuriy.tymchuk(a)me.com> wrote: >>>>> Thatâs why mathematics and programming are two different thingsâ¦ >>>>> >>>>> >>>>> On 11 Jul 2014, at 16:08, Esteban A. Maringolo <emaringolo(a)gmail.com> wrote: >>>>> >>>>> > Usually comparing against floats is not as deterministic as you would >>>>> > expect. And in other dialects you use #equals: instead of #= >>>>> > >>>>> > But in Pharo there is no #equals: and instead there is a #closeTo:, >>>>> > but #closeTo: has an arbitrary decimal precision, more than enough for >>>>> > commong arithmetic. >>>>> > >>>>> > Regards! >>>>> > >>>>> > Esteban A. Maringolo >>>>> > >>>>> > >>>>> > 2014-07-11 10:59 GMT-03:00 Goubier Thierry <thierry.goubier(a)cea.fr>: >>>>> >> :) >>>>> >> >>>>> >> in Smalltalk, the division of two integers is a fraction, not a float. >>>>> >> >>>>> >> i.e. 1/5 is 1/5. >>>>> >> >>>>> >> Thierry >>>>> >> >>>>> >> Le 11/07/2014 15:53, Natalia Tymchuk a Ã©crit : >>>>> >>> >>>>> >>> Hello. >>>>> >>> I found interesting thing: >>>>> >>> Why it is like this? >>>>> >>> >>>>> >>> Best regards, >>>>> >>> Natalia >>>>> >>> >>>>> >> >>>>> >> -- >>>>> >> Thierry Goubier >>>>> >> CEA list >>>>> >> Laboratoire des Fondations des SystÃ¨mes Temps RÃ©el EmbarquÃ©s >>>>> >> 91191 Gif sur Yvette Cedex >>>>> >> France >>>>> >> Phone/Fax: +33 (0) 1 69 08 32 92 / 83 95 >>>>> >> >>>>> > >>>>> >>>>> >>>>> >>>> >>> >> >

July 11, 2014

Re: [Pharo-dev] Division isn't correct

by Luc Fabresse

Hi Natalia, The major problem comes from float memory representation. You can read the beginning of chapter "Fun with Floats" of Deep into Pharo that gives examples of why comparing floats is dangerous. http://rmod.lille.inria.fr/deepIntoPharo/ #Luc 2014-07-11 17:02 GMT+02:00 Natalia Tymchuk <natalia.tymchuk(a)unikernel.net>: > But why > 185/10 = 18.5 -> true? > > On Jul 11, 2014, at 4:40 PM, Norbert Hartl <norbert(a)hartl.name> wrote: > > > Am 11.07.2014 um 16:33 schrieb Yuriy Tymchuk <yuriy.tymchuk(a)me.com>: > > > On 11 Jul 2014, at 16:30, Esteban Lorenzano <estebanlm(a)gmail.com> wrote: > > On 11 Jul 2014, at 16:22, kilon alios <kilon.alios(a)gmail.com> wrote: > > why not round it before comparing it ? looks like an easy enough problem > to fix . I would expect that to be equal. > > > because it wouldnât be correct :) > > > But then why 4/2 = 2? > > > The same reason why > > 4/3 = 8/6 > > :) > > Norbert > > > > > > On Fri, Jul 11, 2014 at 5:18 PM, Yuriy Tymchuk <yuriy.tymchuk(a)me.com> > wrote: > >> Thatâs why mathematics and programming are two different thingsâ¦ >> >> >> On 11 Jul 2014, at 16:08, Esteban A. Maringolo <emaringolo(a)gmail.com> >> wrote: >> >> > Usually comparing against floats is not as deterministic as you would >> > expect. And in other dialects you use #equals: instead of #= >> > >> > But in Pharo there is no #equals: and instead there is a #closeTo:, >> > but #closeTo: has an arbitrary decimal precision, more than enough for >> > commong arithmetic. >> > >> > Regards! >> > >> > Esteban A. Maringolo >> > >> > >> > 2014-07-11 10:59 GMT-03:00 Goubier Thierry <thierry.goubier(a)cea.fr>: >> >> :) >> >> >> >> in Smalltalk, the division of two integers is a fraction, not a float. >> >> >> >> i.e. 1/5 is 1/5. >> >> >> >> Thierry >> >> >> >> Le 11/07/2014 15:53, Natalia Tymchuk a Ã©crit : >> >>> >> >>> Hello. >> >>> I found interesting thing: >> >>> Why it is like this? >> >>> >> >>> Best regards, >> >>> Natalia >> >>> >> >> >> >> -- >> >> Thierry Goubier >> >> CEA list >> >> Laboratoire des Fondations des SystÃ¨mes Temps RÃ©el EmbarquÃ©s >> >> 91191 Gif sur Yvette Cedex >> >> France >> >> Phone/Fax: +33 (0) 1 69 08 32 92 / 83 95 >> >> >> > >> >> >> > > > > >

July 11, 2014