How can I use custom membership functions in ANFIS?

I am trying to use custom MFs in anfis, instead of the preset bellMF?

I have followed the steps in this link, but how do I use it afterwards in my code?

For example in the example provided, we have:

load fuzex1trnData.dat

fis = anfis(fuzex1trnData);

Now how do I use the FIS (customfis) with the custom MF that I created using FuzzyLogicDesigner?

Any help is appreciated.

Answer 1

[Amritesh]

If you have already made FIS, then use fis = anfis(trainingData,options) and in options use that custom FIS.

If not then, first add custom membership function to a FIS like

myFIS = addMF(myFIS,"input1","custmf1",[0 1 2 4 6 8 9 10],'Name',"customMF1");

Documentation Links:

1. https://in.mathworks.com/help/fuzzy/building-fuzzy-inference-systems-using-custom-functions.html
2. https://in.mathworks.com/help/fuzzy/anfis.html

Hope this solves your problem.

[Tooba Shelkh]

I want to train ANFIS on my custom MF. It is not allowing me to do that, it requires me to add built-in MF for that purpose. It does not generate the rules from my custom MF.

[Amritesh]

You can define an initial FIS structure using genfisOptions

genOpt = genfisOptions('GridPartition');
genOpt.NumMembershipFunctions = num;
genOpt.InputMembershipFunctionType = 'cumstomMF1'; % Here you use your custom MF
inFIS = genfis(x,y,genOpt);

You can use name of a custom membership function in the current working folder or on the MATLAB® path in InputMembershipFunctionType.

Have a look at https://in.mathworks.com/help/fuzzy/genfisoptions.html

And, then configure the ANFIS training options

opt = anfisOptions('InitialFIS',inFIS);