From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=unavailable autolearn_force=no version=3.4.4 Path: eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!news.eternal-september.org!news.eternal-september.org!feeder.eternal-september.org!aioe.org!.POSTED!not-for-mail From: "Dmitry A. Kazakov" Newsgroups: comp.lang.ada Subject: Re: Interfacing Ada With Full Runtime Directly to Electronic Chips Date: Tue, 3 Jan 2017 22:41:40 +0100 Organization: Aioe.org NNTP Server Message-ID: References: <9ca07b79-db85-4d4a-b082-61cd75fcc1c8@googlegroups.com> <20f3a379-e76d-4323-8f1a-a1bb77b93d7e@googlegroups.com> <73cc51c6-035f-4622-8952-a7c0f48fbcb2@googlegroups.com> NNTP-Posting-Host: s3c6wwRqkurrfTZpuYYZ+w.user.gioia.aioe.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit X-Complaints-To: abuse@aioe.org User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.6.0 X-Notice: Filtered by postfilter v. 0.8.2 Xref: news.eternal-september.org comp.lang.ada:33029 Date: 2017-01-03T22:41:40+01:00 List-Id: On 2017-01-03 21:50, Shark8 wrote: > On Tuesday, January 3, 2017 at 1:34:31 PM UTC-7, Dmitry A. Kazakov wrote: >> On 2017-01-03 19:02, Shark8 wrote: >>> On Tuesday, January 3, 2017 at 3:34:33 AM UTC-7, Dmitry A. Kazakov wrote: >>>> On 2017-01-03 06:33, Shark8 wrote: >>>> >>>>> That's really interesting, because the system I want to do >>>>> [ultimately] is a ternary computer -- for which tri-state logic is a >>>>> perfect fit. >>>> >>>> Out of curiosity, why tri-state logic and not full four-state one? >>>> Tri-state is incomplete in some operations (e.g. in implication). >>> >>> The completeness of the logic-system depends on which logic-system >>> is being used -- there are several for three-valued logic -- but it is a >>> non-issue because you can use full Boolean logic (e.g.) by defining 0 to >>> be True and ±1 to be False (i.e. using inverse-logic).* >> >> [...] >> >> I see, it is just a ternary system and not logic in the sense of lattice >> and inference, like {False, True, Unknown}. > > You can model True/False/Unknown -- just map each value to one of {1,0,J}, obviously. Maybe > But how would a lattice & inference system look? Esp. at the gate-level. Logic gates? A lattice has "and", "or", "not", obeying de Morgan rules. They are same as Boolean when arguments are Boolean. E.g. the truth table for "and": and F T U --+------ F | F F F T | F T U U | F U U I understood that this has little (if anything at all) to do with the system you had in mind. The similarity of names is coincidental. Considering flow of control in a logical system with "unknown" state. Let you have if A and B then S1; else S2; end if; Let A = U and B = T. Then A and B = U. So both S1 and S2 must be evaluated but their side effects kept aside until some point, where you become certain what path was to choose. Then you commit the effects of this only path. In fuzzy systems it is called defuzzification. I am not familiar with quantum computing, but I guess it is kind of similar to this. You "calculate" all possible states and at some point collapse all of them into just one. Now if you had a forth state you wold follow no path if A and B would evaluate it. So it is "one"/true, "another"/false, "any", "none", a complete set of choices. -- Regards, Dmitry A. Kazakov http://www.dmitry-kazakov.de