Matlab help

Valas

I have given some 3 symbols (images) and I want to classify them into clusters using the nearest neighbour algorithm (according to their mgnitude spectrum). I have already produced their magnitude spectrums and I choose the areas from the spectrum to extract information from ( i summed up all the points in the specific areas ). Then what is the process i have to follow in order to take each one and classify it?

Any hints and tips using matlab funtions would be appreciated

Thanks