Re: What is wrong with OO ?

[Tansel Ersavas <tansel@deep.net>]

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

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