Using (classificationKNN.fit) in Matlab

Hi,

I want to define a set of weights for the distance measure in KNN method. According to the MATLAB help the distance weight function can be a 'equal','inverse','squaredinverse', or a function handle. I tried to define the weights using the following function.

function WGT=gene 
     weights=round(rand(a,b))
     WGT=T
end

However, when I apply KNN the weights does not changed and are equally distributed. My fitting code is

 (fitness=ClassificationKNN.fit(train_attribute,train_class,'Numneighbors',4,'distanceweight',@gene_weights))

Can anyone help with this problem please. Thank you in advance Best Regards