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 X-Received: by 10.224.4.138 with SMTP id 10mr11063996qar.8.1377128003854; Wed, 21 Aug 2013 16:33:23 -0700 (PDT) X-Received: by 10.49.128.97 with SMTP id nn1mr160314qeb.13.1377128003818; Wed, 21 Aug 2013 16:33:23 -0700 (PDT) Path: border1.nntp.dca3.giganews.com!border3.nntp.dca.giganews.com!border1.nntp.dca.giganews.com!nntp.giganews.com!q10no42822qai.0!news-out.google.com!c19ni456qak.0!nntp.google.com!fx3no3928434qab.0!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail Newsgroups: comp.lang.ada Date: Wed, 21 Aug 2013 16:33:23 -0700 (PDT) In-Reply-To: <87zjsar72v.fsf@nl106-137-194.student.uu.se> Complaints-To: groups-abuse@google.com Injection-Info: glegroupsg2000goo.googlegroups.com; posting-host=64.183.207.38; posting-account=zwxLlwoAAAChLBU7oraRzNDnqQYkYbpo NNTP-Posting-Host: 64.183.207.38 References: <87mwoastdi.fsf@nl106-137-194.student.uu.se> <9d7e5c6c-aeb9-4ac1-a7b0-c048061ae4c6@googlegroups.com> <87zjsar72v.fsf@nl106-137-194.student.uu.se> User-Agent: G2/1.0 MIME-Version: 1.0 Message-ID: Subject: Re: RTS graph and "temporal formulas" From: optikos@verizon.net Injection-Date: Wed, 21 Aug 2013 23:33:23 +0000 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable X-Original-Bytes: 5597 Xref: number.nntp.dca.giganews.com comp.lang.ada:183094 Date: 2013-08-21T16:33:23-07:00 List-Id: On Wednesday, August 21, 2013 5:50:55 PM UTC-5, Emanuel Berg wrote: > opt...@verizon.net writes: >=20 > > You turn to the Ada-language Usenet group for a question about > > 1950s mathematics-nomenclature? Oh well. Instead of "get off > > my lawn", I will point you in the right direction, which > > generally leads away from here. :-) >=20 > The reason I posted here is that we had Ada in the course. But your professor utilized C-language's =3D=3D as the logical comparison= in the E->D transition's stimulus-constraint in 7b, not Ada's =3D. :-) > Thanks for the tutorial, very helpful. I will read those pages, > only: the "x :=3D 0" response transition doesn't have a stimuli. Transitions which lack a stimulus are always traversed. The lack of stim= ulus is notated overtly as epsilon. 2 or more epsilon transitions egressin= g from the same state is an ambiguous type of FSA called an NFA. But when = there exists only one epsilon transition as the sole transition egressing f= rom a state, then determinism is effectively preserved. http://en.wikipedia.org/wiki/Nondeterministic_finite_automaton_with_%CE%B5-= moves > The state it comes from has one, so perhaps that should be used? Yes. Epsilon in this idiomatic usage means always traverse this C->A tra= nsition when in state C. > But then, the "A" state has a stimuli (x <=3D 10), and two outgoing > transitions *with* stimuli (x < 5 and x > 11) - how should this be > interpreted? Upon second look, your professor has utilized both Mealy stimulus-constra= int nomenclature (with green logical comparisons as stimulus-constraints on= the transitions of 7a) and Moore response-triggered nomenclature (with pur= ple logical comparisons as characterizations of execution time of the softw= are which executes upon entering a state). Please be very careful with your wording, because sloppy terminology is a= major component in your confusion. The contextual environment has stimuli= ; the FSA does not. The FSA has Mealy-nomenclature stimulus-***constraints= *** (i.e., green logical comparisons on transitions) against which incoming= stimuli from the sensors are matched. State A does not have a stimulus; s= tate A has a Moore-nomenclature response (i.e., purple logical predicate as= a characterization of the execution time of software executed upon entranc= e to State A). Decoder ring that your professor should have provided in the text of Prob= lem 7 or in the class: green: stimulus-constraint (input) purple: [characterization of] response (output) blue: [imperative instruction that implements] response (output) > Last: the clocks - do they start at 0? Yes. In a well designed FSA, there would be an overt pre-A initial state= with epsilon transition whose response is x:=3D0 initialization-to-zero, a= nalogous to the C->A transition reset-to-zero. > Making a transition, that doesn't take any time, does it? That is where I am supplementing my prior posting (where I was hand-wavin= gly oblivious to your current situation at hand). "Taking time" in a state= is precisely what the purple logical comparisons are. The usage of nearly= the same nomenclature 1) for characterization of execution time of the sof= tware executed upon entry to a state [as output] and 2) for the stimulus-co= nstraint [related to comparisons against input] differed only by color is a= n especially cryptic and unwise nomenclature that is inferior to the nomenc= lature of Mealy, Moore, or the modern math utilized in the Wikipedia articl= es to which I directed you. Your professor appears to lump the time it takes to make a transition in wi= th the purple execution-time chararterizations of the state into which the = transition ingresses. Conversely, your professor appears to assume that fa= iled attempts to match the sensors' stimuli to each not-traversed transitio= n egressing from the current state takes zero time (which is incorrect, bec= ause it does take time, unless the clock ticks relatively huge compared to = the overhead of operating the FSA). > --=20 > Emanuel Berg - programmer (hire me! CV below) > computer projects: http://user.it.uu.se/~embe8573 > internet activity: http://home.student.uu.se/embe8573