Hi @amir
There is no built-in function in the Fuzzy Logic Toolbox to accomplish this. Moreover, if the fuzzy inference system (FIS) can indeed produce a specified output, there may be unlimited combinations of inputs in the output manifold that yield exactly that output.
The task is somewhat analogous to solving a system of nonlinear equations; however, the FIS represents only a single nonlinear manifold equation. Therefore, the problem constitutes an underdetermined system.
x1 = (20:0.01:50)';
x2 = x1;
y = x1 + x2;
data= [x1, x2, y];
opt = anfisOptions("DisplayANFISInformation", 0, "DisplayErrorValues", 0, "DisplayStepSize", 0, "DisplayFinalResults", 0);
fis = anfis(data, opt);
out1= evalfis(fis, [20.0 45.0])
out2= evalfis(fis, [25.0 40.0])
out3= evalfis(fis, [30.0 35.0])
out4= evalfis(fis, [32.5 32.5])
out5= evalfis(fis, [35.0 30.0])
out6= evalfis(fis, [40.0 25.0])
out7= evalfis(fis, [45.0 20.0])
gensurf(fis)
xlabel('x1'), ylabel('x2'), zlabel('y')
