Exemplo n.º 1
0
 def test_shape_dim2(self):
     X = numpy.random.randn(10, 3)
     w = numpy.array([[10, 20, 3], [-10, -20, 0.5]])
     for act in ['sigmoid', 'sigmoid4', 'expit', 'identity',
                 'relu', 'leakyrelu']:
         with self.subTest(act=act):
             neu = NeuralTreeNode(w, bias=[-4, 0.5], activation=act)
             pred = neu.predict(X)
             self.assertEqual(pred.shape, (X.shape[0], 2))
Exemplo n.º 2
0
    def test_neural_net_gradient_regression_2(self):
        X = numpy.abs(numpy.random.randn(10, 2))
        w1 = numpy.array([-0.5, 0.8, -0.6])
        noise = numpy.random.randn(X.shape[0]) / 10
        noise[0] = 0
        noise[1] = 0.07
        X[1, 0] = 0.7
        X[1, 1] = -0.5
        y = w1[0] + X[:, 0] * w1[1] + X[:, 1] * w1[2] + noise

        for act in [
                'relu', 'sigmoid', 'identity', 'leakyrelu', 'sigmoid4', 'expit'
        ]:

            with self.subTest(act=act):
                neu = NeuralTreeNode(w1[1:], bias=w1[0], activation=act)
                loss1 = neu.loss(X, y)
                pred1 = neu.predict(X)
                if act == 'relu':
                    self.assertEqualArray(pred1[1:2], numpy.array([0.36]))
                    pred11 = neu.predict(X)
                    self.assertEqualArray(pred11[1:2], numpy.array([0.36]))

                net = NeuralTreeNet(X.shape[1], empty=True)
                net.append(neu, numpy.arange(0, 2))
                ide = NeuralTreeNode(numpy.array([1], dtype=X.dtype),
                                     bias=numpy.array([0], dtype=X.dtype),
                                     activation='identity')
                net.append(ide, numpy.arange(2, 3))
                pred2 = net.predict(X)
                loss2 = net.loss(X, y)

                self.assertEqualArray(pred1, pred2[:, -1])
                self.assertEqualArray(pred2[:, -2], pred2[:, -1])
                self.assertEqualArray(pred2[:, 2], pred2[:, 3])
                self.assertEqualArray(loss1, loss2)

                for p in range(0, 5):
                    grad1 = neu.gradient(X[p], y[p])
                    grad2 = net.gradient(X[p], y[p])
                    self.assertEqualArray(grad1, grad2[:3])
Exemplo n.º 3
0
 def test_neural_tree_node(self):
     self.assertRaise(lambda: NeuralTreeNode([0, 1], 0.5, 'identity2'))
     neu = NeuralTreeNode([0, 1], 0.5, 'identity')
     res = neu.predict(numpy.array([4, 5]))
     self.assertEqual(res, 5.5)
     st = repr(neu)
     self.assertEqual("NeuralTreeNode(weights=array([0., 1.]), "
                      "bias=0.5, activation='identity')", st)
     st = io.BytesIO()
     pickle.dump(neu, st)
     st = io.BytesIO(st.getvalue())
     neu2 = pickle.load(st)
     self.assertTrue(neu == neu2)
Exemplo n.º 4
0
    def test_gradients(self):
        X = numpy.array([0.1, 0.2, -0.3])
        w = numpy.array([10, 20, 3])
        g = numpy.array([-0.7], dtype=numpy.float64)
        for act in [
                'sigmoid', 'sigmoid4', 'expit', 'identity', 'relu', 'leakyrelu'
        ]:
            with self.subTest(act=act):
                neu = NeuralTreeNode(w, bias=-4, activation=act)
                pred = neu.predict(X)
                self.assertEqual(pred.shape, tuple())
                grad = neu.gradient_backward(g, X)
                self.assertEqual(grad.shape, (4, ))
                grad = neu.gradient_backward(g, X, inputs=True)
                self.assertEqual(grad.shape, (3, ))
                ww = neu.training_weights
                neu.update_training_weights(-ww)
                w0 = neu.training_weights
                self.assertEqualArray(w0, numpy.zeros(w0.shape))

        X = numpy.array([0.1, 0.2, -0.3])
        w = numpy.array([[10, 20, 3], [-10, -20, 3]])
        b = numpy.array([-3, 4], dtype=numpy.float64)
        g = numpy.array([-0.7, 0.2], dtype=numpy.float64)
        for act in ['softmax', 'softmax4']:
            with self.subTest(act=act):
                neu = NeuralTreeNode(w, bias=b, activation=act)
                pred = neu.predict(X)
                self.assertAlmostEqual(numpy.sum(pred), 1.)
                self.assertEqual(pred.shape, (2, ))
                grad = neu.gradient_backward(g, X)
                self.assertEqual(grad.shape, (2, 4))
                grad = neu.gradient_backward(g, X, inputs=True)
                self.assertEqual(grad.shape, (3, ))
                ww = neu.training_weights
                neu.update_training_weights(-ww)
                w0 = neu.training_weights
                self.assertEqualArray(w0, numpy.zeros(w0.shape))
Exemplo n.º 5
0
 def test_shape_dim2(self):
     X = numpy.random.randn(10, 3)
     w = numpy.array([[10, 20, 3], [-10, -20, 0.5]])
     first = None
     for act in [
             'sigmoid', 'sigmoid4', 'expit', 'identity', 'relu', 'leakyrelu'
     ]:
         with self.subTest(act=act):
             neu = NeuralTreeNode(w, bias=[-4, 0.5], activation=act)
             pred = neu.predict(X)
             self.assertEqual(pred.shape, (X.shape[0], 2))
             text = str(neu)
             self.assertIn('NeuralTreeNode(', text)
             if first is None:
                 first = neu
             else:
                 self.assertFalse(neu == first)
             self.assertEqual(neu.ndim, 3)
             loss = neu.loss(X[0], 0.)
             self.assertEqual(loss.shape, (2, ))
             loss = neu.loss(
                 X, numpy.zeros((X.shape[0], 1), dtype=numpy.float64))
             self.assertEqual(loss.shape, (10, 2))