On 11 juil. 2014, at 17:02, Natalia Tymchuk <natalia.tymc...@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 <norb...@hartl.name> wrote: > >> >> Am 11.07.2014 um 16:33 schrieb Yuriy Tymchuk <yuriy.tymc...@me.com>: >> >>> >>> On 11 Jul 2014, at 16:30, Esteban Lorenzano <esteba...@gmail.com> wrote: >>> >>>> On 11 Jul 2014, at 16:22, kilon alios <kilon.al...@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 wouldn’t 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.tymc...@me.com> >>>>> wrote: >>>>> That’s why mathematics and programming are two different things… >>>>> >>>>> >>>>> On 11 Jul 2014, at 16:08, Esteban A. Maringolo <emaring...@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.goub...@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 écrit : >>>>> >>> >>>>> >>> Hello. >>>>> >>> I found interesting thing: >>>>> >>> Why it is like this? >>>>> >>> >>>>> >>> Best regards, >>>>> >>> Natalia >>>>> >>> >>>>> >> >>>>> >> -- >>>>> >> Thierry Goubier >>>>> >> CEA list >>>>> >> Laboratoire des Fondations des Systèmes Temps Réel Embarqués >>>>> >> 91191 Gif sur Yvette Cedex >>>>> >> France >>>>> >> Phone/Fax: +33 (0) 1 69 08 32 92 / 83 95 >>>>> >> >>>>> > >>>>> >>>>> >>>>> >>>> >>> >> >
