In the code you provided, a class called Linear
is defined as a subclass of keras.layers.Layer
. This class represents a linear layer in a neural network, with the equation y = w.x + b
. Here's a breakdown of the code:
-
The
__init__
method is the constructor of the class. It initializes the object and sets the number of units (neurons) for the linear layer. -
The
build
method is called when the layer is connected to an input for the first time. It is used to define the weights of the layer. Within this method,self.w
andself.b
are created as trainable weights usingself.add_weight
. The shape ofself.w
is(input_shape-1, self.units)
whereinput_shape
represents the number of input features. The shape ofself.b
is(self.units,)
, matching the number of units specified. -
The
call
method defines the forward pass of the layer. It takes the inputinputs
, performs matrix multiplication between the input and the weight matrixself.w
, and adds the biasself.b
. The result is returned as the output of the layer. -
After the class definition, an instance of the
Linear
layer calledlinear_layer
is created withunits=4
. -
Finally, the code applies the
linear_layer
to a tensor of ones with shape(2, 2)
. This is done by callinglinear_layer(tf.ones((2, 2)))
. The result is stored iny
.
In summary, the code defines a custom linear layer that can be used as a building block in a neural network. It sets up the layer's weights in the build
method and performs the forward pass computation in the call
method. The instance of the Linear
layer is then used to apply the layer to a tensor of ones, generating the output y
.