xdc_git_python_20210511/tutorials-master/theanoTUT/theano8_Layer_class.py

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# 8 - define Layer class
"""
Please note, this code is only for python 3+. If you are using python 2+, please modify the code accordingly.
"""
from __future__ import print_function
import theano
import theano.tensor as T
import numpy as np


class Layer(object):
    def __init__(self, inputs, in_size, out_size, activation_function=None):
        self.W = theano.shared(np.random.normal(0, 1, (in_size, out_size)))
        self.b = theano.shared(np.zeros((out_size, )) + 0.1)
        self.Wx_plus_b = T.dot(inputs, self.W) + self.b
        self.activation_function = activation_function
        if activation_function is None:
            self.outputs = self.Wx_plus_b
        else:
            self.outputs = self.activation_function(self.Wx_plus_b)

"""
to define the layer like this:
l1 = Layer(inputs, 1, 10, T.nnet.relu)
l2 = Layer(l1.outputs, 10, 1, None)
"""