Re: Membership functions.

Earl Cox (ecox@metus.com)
Fri, 25 Jun 1999 06:13:04 +0200 (MET DST)

I have a fuzzy set editor, written in 32-bit Visual Basic that uses the DLL
libraries from The Fuzzy Systems Handbook (2nd Edition). I would be glad to
let you have it. Send me your email address and I'll send it as an
attachment. The only draw back, is the use of the Olectra OCX graphics
package to display the membership functions. Given the over-all framework,
however, with the graphics display functions isolated in a single procedure,
you should be able to substitute another graphics package very easily.

BTW, Ted and Jill's book is really good and doesn't get nearly the attention
it deserves. They both are knowledgeable experts in the field. I especially
like their object oriented fuzzy system outlined in Chapter 9. But overall
the entire structure of the book is well conceived and written with a good
sense of authority.

Earl

news wrote in message ...
>Earl Cox wrote in message ...
>>You should not be surprised that changing the shape of a knowledge base's
>>fuzzy sets changes the output control surface of the rules. After all, it
>is
>>the fuzzy sets that specify the semantics of the rule. If you change the
>>shape of a fuzzy set, you change the semantics of the knowledge. The fact
>>that the organizational framework -- the rules -- remain the same is
>>immaterial. When you change the topology (or, more properly, the
>morphology)
>>of the fuzzy sets, you change the way the collection of rules behave, you
>>change how truth membership grades are transferred, and you change how the
>>solution control surface is constructed.
>>
>>A very simple expert system shows this. Consider a weight estimating
system
>>of one fuzzy rule,
>>
>> if height is Tall then weight is Heavy
>>
>>where Tall is a linear increasing fuzzy set and weight is a right-facing
>>S-curve. Running this rule will give us an estimate of weight. If you now
>>change the shape of Tall to a skewed S-curve, you will get a very
different
>>weight estimate. In fact, without changing the rule, you can generate many
>>different weight estimating models simply by changing the fuzzy set
shapes.
>>
>>Just a comment.
>>Earl
>>
>>
>>Pramit 'Jake' Sarma wrote in message ...
>>>A very useful experimental way to check the 'goodness' of MF geometry is
>>>by inspecting the input/output surface generated by the fuzzy
>>>inferencer with a given rule-base. There can be striking differences in
>>>the surface for different MF shapes for the *identical* rule-base.
>>>
>
>
>Has anyone built a public domain or freeware member function editor?
>Something simple that reads and writes a text file that describes the fuzzy
>set's member functions, using triangular or S/Z representations, and lets
>the user graphically inspect and alter the set?
>
>I'm kinda new to the group, but I've been reading comp.ai.fuzzy for a
couple
>of weeks and have been reading "Fuzzy Logic for Real World Design" by Heske
>& Heske, for a project I'm working on. Unless I find something to help do
>this for me, it looks like my first real task will be to design a general
>purpose fuzzy set editor... seems like that wheel would have been invented
>by now somewhere.
>
>Any ideas?
>
>Thanks,
>JH
>PS-(to reply via email, remove the SPAM-WHACKER from my email)
>
>

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