I college students, just contact computer neurology, doing homework, and then the hopfield network professor this part is not very clear, want to ask a question:
The Hopfield Network, weighting matrix algorithm is shown in figure:

I don't quite understand that formula inside a is what meaning, if say I now have three sets of training data, I want to get three of them combined weight matrix, should how to calculate? Should be in each training data xi * xj, then together, divided by 3? The case is likely to work out the weight matrix are decimal? Weighting matrix in my mind can only contain 1 or 1, you can have a decimal? Then can you tell me if it's not as I said above method, the correct method is what? thank you