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# One function returns the correct results, the opposite not. Why?

## One function returns the correct results, the opposite not. Why?

(OP)

I have the following function that checks the pixels from x that have the membership value near 1 and sets those pixels in x to 1 and return them back. The works pretty well for me:

function c = core(x, y)
tolerance = 0.01;
[ii,jj]=find (abs(y)-1 <= tolerance);
x(ii,jj)=1; % set pixels in x with y=1 to 1
idx=[ii,jj]; % indexes of pixels with y=1
c=x(abs(y)-1 <= tolerance); % values of pixels
end

Now, to the opposite function below. I just want to check the pixels that have membership values values not equal to one and since in my case I don't have exactly value 1 and this used tolerance. I wrote what I think is the opposite of the above, but my output is an empty matrix. Why is that? What should I change in the function below?

function s = support(x, y)
tolerance = 0.01;
[ii,jj]= find (abs(y)-1 > tolerance);
x(ii,jj)=0; % set pixels in x with y~=1 to 0
idx=[ii,jj]; % indexes of pixels with y~=1
s=x(abs(y)-1 > tolerance); % values of pixels
end

Thanks.

### RE: One function returns the correct results, the opposite not. Why?

Brackets look fine to me. Code also works fine for me:

#### CODE --> Matlab

>> x = [1 2 3 4 5 6];
>> y = [1.001 1.5 1.005 4 0.995 0.999];
>> core(x, y)

ans =

1     1     1     1

>> support(x, y)

ans =

0     0 

Not sure why you'd want to do this, but the two functions certainly perform opposite functions and neither returns an empty matrix (unless of course, no values satisfy the condition).

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