'X : A Theano matrix of input examples.
Each row is an example.
Each column is a feature.
Returns:
H: A Theano matrix of hidden unit values
y_hat: A Theano vector of outputs. Output i is the predicted
value for example i.'

def fprop(self, X):

    H = T.nnet.sigmoid(T.dot(X, self.W_hid))
    y_hat = T.dot(H, self.w_out)
    return (H, y_hat)
