Artificial Intelligence By Example
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Linear separability was achieved

Bear in mind that the whole purpose of this feedforward network with backpropagation through a cost function was to transform a linear non-separable function into a linearly separable function to implement classification of features presented to the system. In this case, the features had 0 or 1 value.

One of the core goals of a layer in a neural network is to make the input make sense, meaning to be able to separate one kind of information from another.

h1 and h2 will produce the Cartesian coordinate linear separability training axis, as implemented in the following code:

h1= h1 * -b1 
h2= h2 * b2
print(h1,h2)

Running the program provides a view of the nonlinear input values once they have been trained by the hidden layers. The nonlinear values then become linear values in a linearly separable function:

linearly separability through cartesian training -1.0000000000000004 1.0000000000000004
linearly separability through cartesian training -0.0 0.0
linearly separability through cartesian training -0.0 1.0000000000000004
linearly separability through cartesian training -0.0 1.0000000000000004
epoch: 10 optimization 0 w1: 0.5 w2: 1.0 w3: 1.0 w4: 0.5 b1: -1.0 b2: 1.0

The intermediate result and goal are not a bunch of numbers on a screen to show that the program works. The result is a set of Cartesian values that can be represented in the following linearly separated graph:

We have now obtained a separation between the top values (empty circle) representing the intermediate values of the 1,0 and 0,1 inputs, and the bottom values representing the 1,1 and 0,0 inputs. We now have clouds on top and trees below the line that separates them.

The layers of the neural network have transformed nonlinear values into linear separable values, making classification possible through standard separation equations, such as the one in the following code:

#IV. threshold II and OUTPUT y
y=h1+h2 # logical separation
if(y<1 and pred>=0 and pred<2):
result[pred]=1

if(y>=1 and pred>=2 and pred<4):
result[pred]=1

The ability of a neural network to make non-separable information separable and classifiable represents one of the core powers of deep learning. From this technique, many operations can be performed on data, such as subset optimization.