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=0.2 required=5.0 tests=BAYES_00,INVALID_MSGID, REPLYTO_WITHOUT_TO_CC autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 109fba,b87849933931bc93 X-Google-Attributes: gid109fba,public X-Google-Thread: f43e6,b87849933931bc93 X-Google-Attributes: gidf43e6,public X-Google-Thread: fac41,b87849933931bc93 X-Google-Attributes: gidfac41,public X-Google-Thread: 1108a1,b87849933931bc93 X-Google-Attributes: gid1108a1,public X-Google-Thread: 11cae8,b87849933931bc93 X-Google-Attributes: gid11cae8,public X-Google-Thread: 103376,b87849933931bc93 X-Google-Attributes: gid103376,public X-Google-Thread: 114809,b87849933931bc93 X-Google-Attributes: gid114809,public From: Tansel Ersavas Subject: Re: What is wrong with OO ? Date: 1996/12/15 Message-ID: <32B4D921.7D84@deep.net>#1/1 X-Deja-AN: 204319414 references: <590dsq$gr3@news4.digex.net> content-type: text/plain; charset=us-ascii organization: RASE Inc. mime-version: 1.0 reply-to: tansel@deep.net newsgroups: comp.lang.c++,comp.lang.smalltalk,comp.lang.eiffel,comp.lang.ada,comp.lnag.java,comp.object,comp.software-eng x-mailer: Mozilla 3.0 (Win95; U) Date: 1996-12-15T00:00:00+00:00 List-Id: Ell wrote: > If you say that OO can be used for simulation and that SIMULA was the > ancestor of other OOPLs and its purpose was to simulate, then how can you > say above that modelling the real world is simply "simulation" not OO? > Simulation is a technique that is used to make educated guesses about reality. In fact, an appealing approach for OOA would be to simulate the problem domain to develop a better understanding of it (however, for most, this is only in theory, because they don't have such powerful tools to simulate the problem domain as soon as necessary details are captured about it. Our Snowball Rapid Systems Engineering Tool can be used for this purpose). In the sciences, there are three basic approaches to understand the reality. These are: . Experimentation . Analysis . Simulation Experimentation develops the best understanding in most cases, but it is usually very expensive, dangerous, or even impossible (such as a space shuttle journey to Mars) Analysis is where we use mathematical techniques to model, then using this model to predict. This works when these types of techniques are available and practical. It also makes strong assumptions about the model which is rarely true in the real world Simulation is an experimentation technique where we use a simulated model instead of the real case for the experimentation. There are advantages and drawbacks of this approach. There are three types of simulation: .Continuous simulation (much like analog computers) .Discrete simulation (such as in activity oriented or event oriented simulation systems) .Object oriented simulation (can be viewed as a special case of OOP, requires time related extensions) My point is: there are many people trying to simulate the real world and they don't use OO. They don't need to use OO, because there are many non-OO simulation packages (such as the continuous and discrete simulation packages). However, IME people benefit a lot when they use OO in large simulations. One of my assignments was to develop a financial modeling tool that would include simulation for an insurance company, and I used OOS with great success in that area. I was involved in a few more projects that were simulations, or involved simulations, so I know that it is much easier to model it in an OO environment, especially if it is a big - complex one. It is up to the team or the person to choose the technique that they want to employ simulation, but I highly recommend OO for simulations. Tansel ----------------------------------------------------------------------- RASE Inc. Clark NJ USA Voice: (908) 396 7145 mailto:tansel@rase.com Fax: (908) 382 1383 http://www.rase.com/ ----Sufficiently advanced technology is indistinguishable from magic--- -------------------------------A.C. Clarke-----------------------------