How to know that each of the output is computed when the input is belong for specific range and print it in the same output?

Hello everyone, I need a help in my code which I built it to use it in my Fuzzy Logic research paper.

The following is a function that I buit it up:

function MF1=evalMF1(x)

global L M H


MF1=[];
 
MF = @(x,z) max(min([(x-z(1))/(z(2)-z(1)), (z(3)-x)/(z(3)-(z(2)))]),0);

if(x>=L(1)&& x<=L(3))
   MF1= [MF1 MF(x,L)] ;
end
if(x>=M(1)&& x<=M(3))
   MF1= [MF1 MF(x,M)] ;
end
if(x>=H(1)&& x<=H(3))
   MF1= [MF1 MF1(x,H)] ;
end

end

Now the following code I use it to recall the function:

% MF for input
global L M H;
       L=[0 10 20] ;
       M= [15 25 35] ;
       H= [30 40 50] ; 
       
In  = evalMF1(16)

For example the output of the above In = evalMF1(16) is

In =

0.4000 0.1000

Now my question is the following:

How can I add to the output result of "In = evalMF1(16)" the range (In the other meaning it is the lingusitic varibale i.e L, M,H) that are each of the output belong to. For the above example the output that I need:

In =

L M

0.4000 0.1000

thats means 0.4 is computed when x belongs to L and 0.1is computed when x belongs to M

in this exapmle when x=16 , two of MF1 was computed, the first MF1 is computed when x belongs to L range, the second MF1 is computed when x belongs to M

If it is hard to use combinations of letters and numbers, we can donate to the L for exapmle L= 1 and so on... But it is better to be letters

I appreciate the any help. Thanks

[Rik]

Global variables are very hard to debug and almost never needed to solve the problem. They often cause more problems than they solve.

This is essentially looking up a value from a lookup table.

What exactly is your question? How to add a line to your lookup table?

Answer 1

[rumin diao]

you could add a new variable in the function and use it to return 'L M H', i've added a variable 'Belong' and here's the code:

% MF for input
global L M H;
       L=[0 10 20] ;
       M= [15 25 35] ;
       H= [30 40 50] ; 
       
[Belong In]  = evalMF1(16)



function [Belong MF1]=evalMF1(x)

global L M H


MF1=[];
Belong = [];
 
MF = @(x,z) max(min([(x-z(1))/(z(2)-z(1)), (z(3)-x)/(z(3)-(z(2)))]),0);

if(x>=L(1)&& x<=L(3))
   Belong = [Belong 'L  '];
   MF1= [MF1 MF(x,L)] ;
end
if(x>=M(1)&& x<=M(3))
    Belong = [Belong 'M  '];
   MF1= [MF1 MF(x,M)] ;
end
if(x>=H(1)&& x<=H(3))
    Belong = [Belong 'H  '];
   MF1= [MF1 MF1(x,H)] ;
end

end

and in this way the output is:

is this what you need?

[M]

@rumin diao Thank you so much, But try another input for example 30, the code will not work?

[M]

@rumin diao I got the following error:

Index in position 1 exceeds array bounds (must not exceed 1).

[M]

@rumin diao

[M]

Hi @Rik, Do you have any idea about this error please?

[rumin diao]

your code in the third part of the function may be wrong, you may want:

if(x>=H(1)&& x<=H(3))
    Belong = [Belong 'H  '];
   MF1= [MF1 MF(x,H)] ;
end