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=1.2 required=5.0 tests=BAYES_00,FROM_WORDY, INVALID_MSGID autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: fac41,e01bd86884246855 X-Google-Attributes: gidfac41,public X-Google-Thread: 103376,fb1663c3ca80b502 X-Google-Attributes: gid103376,public From: "Ken Garlington" Subject: Re: Interresting thread in comp.lang.eiffel Date: 2000/07/14 Message-ID: #1/1 X-Deja-AN: 646162352 References: <8ipvnj$inc$1@wanadoo.fr> <8j67p8$afd$1@nnrp1.deja.com> <39573CAB.BB90DF92@gecm.com> <8j8ek0$24la$3@ID-9852.news.cis.dfn.de> <3957ED3E.E64E7390@lmco.com> <8k8orn$1tlh9$1@ID-9852.news.cis.dfn.de> <94S95.9936$7%3.667320@news.flash.net> <8kl13r$2qd1s$1@ID-9852.news.cis.dfn.de> X-Priority: 3 X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6600 X-Complaints-To: abuse@flash.net X-Trace: news.flash.net 963542744 216.215.65.127 (Thu, 13 Jul 2000 21:45:44 CDT) Organization: FlashNet Communications, http://www.flash.net X-MSMail-Priority: Normal NNTP-Posting-Date: Thu, 13 Jul 2000 21:45:44 CDT Newsgroups: comp.lang.ada,comp.lang.eiffel Date: 2000-07-14T00:00:00+00:00 List-Id: "Joachim Durchholz" wrote in message news:8kl13r$2qd1s$1@ID-9852.news.cis.dfn.de... > Ken Garlington wrote: > > > > I guess I'd like to see an example that actually captured something > > other than software. It's not perfect, but just by concidence I have > > a dataset that represents something vaguely similar to the parameters > > of interest in the Ariane 5 system. If you go to > > > > http://home.flash.net/~kennieg/yf22/crash.html > > > > and scroll down the page, you will see a figure titled YF-22A Accident > > Sequence. Perhaps if you could post Eiffel code that would detect that > > pilot-induced oscillation would have occured given this test case, I > > could understand your confidence in the DbC tecnique better. > > Hmm... I didn't really understand what the report says. It looks like an > oscillation in a self-regulating loop (or whatever this is called in > English cybernetic > theory), with the pilot in the loop somewhere, but I don't know what > parameters should have been detected - I don't now enough about English > aviation terminology and cybernetics to pinpoint what exactly should > have been checked. So what you're saying is: without specific knowledge in this domain, you're finding it difficult to understand how to write the proper contract? Would it be fair to say that if you were a software engineer analyzing an existing module contract, and you were given this figure, you might also have difficulties?