예제 #1
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    def test_add_node(self):
        g = Genome(1, 1)

        # Test adding nodes
        msg = 'Node added incorrectly!'

        g.add_connection(0, 1)
        g.add_node(0)
        self.assertEqual(len(g.get_nodes()), 3, msg)
        self.assertEqual(len(g.get_connections()), 3, msg)
        self.assertFalse(g.get_connections()[0].expressed, msg)
        self.assertTrue(g.get_connections()[1].expressed, msg)
        self.assertTrue(g.get_connections()[2].expressed, msg)
        self.assertEqual(g.get_connections()[0].weight,
                         g.get_connections()[1].weight, msg)
        self.assertEqual(g.get_connections()[2].weight, 1.0, msg)
        self.assertEqual(g.get_nodes()[2].activation,
                         activations.modified_sigmoid, msg)

        g.add_node(1, activation=activations.absolute)
        self.assertEqual(len(g.get_nodes()), 4, msg)
        self.assertEqual(len(g.get_connections()), 5, msg)
        self.assertFalse(g.get_connections()[1].expressed, msg)
        self.assertTrue(g.get_connections()[3].expressed, msg)
        self.assertTrue(g.get_connections()[4].expressed, msg)
        self.assertEqual(g.get_connections()[1].weight,
                         g.get_connections()[3].weight, msg)
        self.assertEqual(g.get_connections()[4].weight, 1.0, msg)
        self.assertEqual(g.get_nodes()[3].activation, activations.absolute,
                         msg)
예제 #2
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    def test_mutate_shift_weight(self):
        g = Genome(1, 1)
        steps = [0.1, 0.2, 0.3, 0.4, 0.5, 1.0, 5.0]
        error_margin = 0.000000000001

        msg = 'Failed to shift weight correctly!'

        # Test with one connection
        g.add_connection(0, 1, weight=0.0)
        for step in steps:
            current_weight = g.get_connections()[0].weight
            g.mutate_shift_weight(step=step)
            self.assertNotEqual(g.get_connections()[0].weight, current_weight,
                                msg)
            self.assertAlmostEqual(abs(g.get_connections()[0].weight -
                                       current_weight),
                                   step,
                                   delta=error_margin)

        # Test with multiple connections
        g.add_node(0)
        for step in steps:
            before = [c.weight for c in g.get_connections()]
            g.mutate_shift_weight(step=step)
            after = [c.weight for c in g.get_connections()]
            self.assertNotEqual(before, after, msg)
예제 #3
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    def test_connections_at_max(self):
        g = Genome(2, 2)

        msg = 'Connections not at max and should be!'
        msg2 = 'Connections at max and shouldn\'t be!'

        # Test with no hidden nodes
        self.assertFalse(g.connections_at_max(), msg)
        g.add_connection(0, 2)
        g.add_connection(0, 3)
        g.add_connection(1, 2)
        self.assertFalse(g.connections_at_max(), msg)
        g.add_connection(1, 3)
        self.assertTrue(g.connections_at_max(), msg2)

        # Test with hidden nodes
        g.add_node(0)
        self.assertFalse(g.connections_at_max(), msg)
        g.add_connection(1, 4)
        g.add_connection(4, 3)
        self.assertTrue(g.connections_at_max(), msg2)
        g.add_node(6)
        self.assertFalse(g.connections_at_max(), msg)
        g.add_connection(0, 5)
        g.add_connection(5, 2)
        g.add_connection(5, 3)
        self.assertTrue(g.connections_at_max(), msg2)
예제 #4
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    def test_copy(self):
        g = Genome(2, 2)

        # Test to make sure the copy is the same as the original
        msg = 'Copy is different from the original!'
        g.add_connection(0, 2)
        g.add_connection(0, 3)
        g.add_node(0)
        gc = g.copy()
        self.assertEqual(len(g.get_nodes()), len(gc.get_nodes()), msg)
        self.assertEqual(len(g.get_connections()), len(gc.get_connections()),
                         msg)
        for i in range(len(g.get_connections())):
            self.assertEqual(g.get_connections()[i].weight,
                             gc.get_connections()[i].weight, msg)

        # Test to make sure the copy doesn't change when the original does
        msg = 'Copy changes when original changes!'
        g.add_node(1)
        g.get_connections()[0].weight = 50
        self.assertNotEqual(len(g.get_nodes()), len(gc.get_nodes()), msg)
        self.assertNotEqual(len(g.get_connections()),
                            len(gc.get_connections()), msg)
        self.assertNotEqual(g.get_connections()[0].weight,
                            gc.get_connections()[0].weight, msg)
예제 #5
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    def test_adjust_population_fitness(self):
        msg = 'Adjusted fitness incorrectly!'

        e = Ecosystem(threshold=0.5, dc=1.0, ec=1.0, wc=0.4)

        # Create genomes
        g = Genome(2, 2)
        g2 = Genome(2, 2)
        g3 = Genome(2, 2)

        # Add connections and/or nodes
        g.add_connection(0, 2, weight=1.0)
        g.add_connection(0, 3, weight=1.0)
        g.add_connection(1, 2, weight=1.0)

        g2.add_connection(0, 2, weight=0.9)
        g2.add_connection(0, 3, weight=1.0)
        g2.add_connection(1, 2, weight=1.0)
        g2.add_connection(1, 3, weight=1.0)

        g3.add_connection(0, 2, weight=0.1)
        g3.add_connection(0, 3, weight=1.0)
        g3.add_connection(1, 2, weight=1.0)
        g3.add_connection(1, 3, weight=1.0)
        g3.add_node(0)
        g3.add_node(1)
        g3.add_node(2)
        g3.add_connection(0, 6, weight=1.0)
        g3.add_connection(1, 5, weight=1.0)

        g4 = copy.copy(g3)
        g4.add_node(3)

        # Set genome fitness
        g.fitness = 10
        g2.fitness = 12
        g3.fitness = 22
        g4.fitness = 24

        # Test to make sure it doesn't change if there are no different genomes
        e.add_genome(g)
        e.adjust_population_fitness()
        self.assertEqual(g.fitness, 10, msg)

        e.add_genome(g2)
        e.adjust_population_fitness()
        self.assertEqual(g.fitness, 10, msg)
        self.assertEqual(g2.fitness, 12, msg)

        # Test to make sure the fitness does change when there are different genomes
        e.add_genome(g3)
        e.add_genome(g4)
        e.adjust_population_fitness()
        self.assertEqual(g.fitness, 5, msg)
        self.assertEqual(g2.fitness, 6, msg)
        self.assertEqual(g3.fitness, 11, msg)
        self.assertEqual(g4.fitness, 12, msg)
예제 #6
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    def test_mutate_random_weight(self):
        g = Genome(1, 1)

        msg = 'Failed to set random connection weight!'

        # Test with one connection
        g.add_connection(0, 1, weight=5)
        g.mutate_random_weight()
        self.assertNotEqual(g.get_connections()[0].weight, 5, msg)
        self.assertTrue(-1.0, g.get_connections()[0].weight <= 1.0)

        # Test with multiple connections
        g.add_node(0)
        before = [c.weight for c in g.get_connections()]
        g.mutate_random_weight()
        after = [c.weight for c in g.get_connections()]
        self.assertNotEqual(before, after, msg)
예제 #7
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    def test_add_genome(self):
        e = Ecosystem()

        # Test to make sure it creates a new species if there aren't any
        msg = 'Failed to create new species with genome!'
        g = Genome(2, 2)
        g.add_connection(0, 2, weight=0.4)
        g.add_connection(0, 3, weight=0.4)
        g.add_connection(1, 2, weight=0.4)
        g.add_connection(1, 3, weight=0.4)
        self.assertEqual(len(e.species), 0, msg)
        e.add_genome(g)
        self.assertEqual(len(e.species), 1, msg)
        self.assertEqual(e.species[0].representative, g, msg)
        self.assertEqual(e.species[0][0], g, msg)
        self.assertEqual(len(e.get_population()), 1, msg)

        # Test to make sure it adds the genome to the same species if they are close
        msg = 'Failed to add genome to species correctly!'
        g2 = Genome(2, 2)
        g2.add_connection(0, 2, weight=0.3)
        g2.add_connection(0, 3, weight=0.4)
        g2.add_connection(1, 2, weight=0.4)
        g2.add_connection(1, 3, weight=0.4)
        e.add_genome(g2)
        self.assertEqual(len(e.species), 1, msg)
        self.assertEqual(e.species[0].representative, g, msg)
        self.assertEqual(e.species[0][1], g2, msg)
        self.assertEqual(len(e.get_population()), 2, msg)

        # Test to make sure a new species is created if the genome is distant from the current species
        msg = 'Failed to create new species with genome!'
        g3 = Genome(2, 2)
        g3.add_connection(0, 2, weight=0.3)
        g3.add_connection(0, 3, weight=0.4)
        g3.add_connection(1, 2, weight=0.4)
        g3.add_connection(1, 3, weight=0.4)
        g3.add_node(0)
        g3.add_node(1)
        g3.add_node(2)
        g3.add_node(3)
        e.add_genome(g3)
        self.assertEqual(len(e.species), 2, msg)
        self.assertEqual(e.species[1].representative, g3, msg)
        self.assertEqual(e.species[1][0], g3, msg)
        self.assertEqual(len(e.get_population()), 3, msg)
예제 #8
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    def test_mutate_toggle_connection(self):
        g = Genome(1, 1)

        msg = 'Failed to toggle connection!'

        # Test with one connection
        g.add_connection(0, 1)
        g.mutate_toggle_connection()
        self.assertFalse(g.get_connections()[0].expressed, msg)
        g.mutate_toggle_connection()
        self.assertTrue(g.get_connections()[0].expressed, msg)

        # Test with multiple connections
        g.add_node(0)
        before = [c.expressed for c in g.get_connections()]
        g.mutate_toggle_connection()
        after = [c.expressed for c in g.get_connections()]
        self.assertNotEqual(before, after, msg)
예제 #9
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    def test_get_node_max_distance(self):
        g = Genome(2, 2)

        # Test to make sure empty genomes return the correct values for output nodes
        msg = 'Disconnected output node returned invalid value!'
        self.assertEqual(g.get_node_max_distance(g.get_node(2).id), -1, msg)
        self.assertEqual(g.get_node_max_distance(g.get_node(3).id), -1, msg)

        # Add nodes and connections
        g.add_connection(0, 2, weight=-0.7)
        g.add_connection(0, 3, weight=-0.1)
        g.add_connection(1, 2, weight=0.5)
        g.add_connection(1, 3, weight=0.9)
        g.add_node(0)
        g.add_node(2)
        g.add_connection(4, 5, 0.5)

        msg = 'Incorrect node max distance!'

        # Test the values of each node distance to make sure they are correct
        correct_distances = [0, 0, 3, 1, 1, 2]
        for node, distance in zip(g.get_nodes(), correct_distances):
            self.assertEqual(g.get_node_max_distance(node.id), distance, msg)

        # Add a node and test again
        g.add_node(8)
        correct_distances = [0, 0, 4, 1, 1, 3, 2]
        for node, distance in zip(g.get_nodes(), correct_distances):
            self.assertEqual(g.get_node_max_distance(node.id), distance, msg)

        # Add connection and test again
        g.add_connection(6, 3)
        correct_distances = [0, 0, 4, 3, 1, 3, 2]
        for node, distance in zip(g.get_nodes(), correct_distances):
            self.assertEqual(g.get_node_max_distance(node.id), distance, msg)

        # Test genome with connection loop
        msg = 'Genome failed to handle connection loop!'

        g2 = Genome(1, 1)
        g2.add_connection(0, 1)
        g2.add_node(0)
        g2.add_node(0)
        g2.add_node(1)
        g2.add_connection(3, 2)
        g2.add_connection(4, 3)
        correct_distances = [0, 4, 3, 3, 3]
        for node, distance in zip(g2.get_nodes(), correct_distances):
            self.assertEqual(g2.get_node_max_distance(node.id), distance, msg)
예제 #10
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    def test_add_connection(self):
        g = Genome(2, 2)

        # Test connecting input and output nodes
        msg = 'Failed connection to output node!'
        g.add_connection(0, 2)
        self.assertEqual(len(g.get_connections()), 1, msg)
        self.assertEqual(g.get_connections()[0].in_node, 0, msg)
        self.assertEqual(g.get_connections()[0].out_node, 2, msg)

        g.add_connection(0, 3)
        self.assertEqual(len(g.get_connections()), 2, msg)
        self.assertEqual(g.get_connections()[1].in_node, 0, msg)
        self.assertEqual(g.get_connections()[1].out_node, 3, msg)

        g.add_connection(1, 2)
        self.assertEqual(len(g.get_connections()), 3, msg)
        self.assertEqual(g.get_connections()[2].in_node, 1, msg)
        self.assertEqual(g.get_connections()[2].out_node, 2, msg)

        g.add_connection(1, 3, 0.5)
        self.assertEqual(len(g.get_connections()), 4, msg)
        self.assertEqual(g.get_connections()[3].in_node, 1, msg)
        self.assertEqual(g.get_connections()[3].out_node, 3, msg)
        self.assertEqual(g.get_connections()[3].weight, 0.5, msg)

        # # Test connecting to hidden nodes
        msg = 'Failed connection to hidden node!'
        g.add_node(0)
        g.add_connection(1, 4, 0.7)
        self.assertEqual(len(g.get_connections()), 7, msg)
        self.assertEqual(g.get_connections()[6].in_node, 1, msg)
        self.assertEqual(g.get_connections()[6].out_node, 4, msg)
        self.assertEqual(g.get_connections()[6].weight, 0.7, msg)

        g.add_node(2)
        g.add_connection(4, 5, 0.9)
        self.assertEqual(len(g.get_connections()), 10, msg)
        self.assertEqual(g.get_connections()[9].in_node, 4, msg)
        self.assertEqual(g.get_connections()[9].out_node, 5, msg)
        self.assertEqual(g.get_connections()[9].weight, 0.9, msg)

        # Test to make sure it catches invalid parameters
        msg = 'Invalid parameters not caught!'

        # Nodes that don't exist
        invalid_nodes = range(10, 15)
        for n1 in invalid_nodes:
            for n2 in invalid_nodes:
                with self.assertRaises(AssertionError, msg=msg):
                    g.add_connection(n1, n2)

        # Duplicate connections
        for conn in g.get_connections():
            with self.assertRaises(AssertionError, msg=msg):
                g.add_connection(conn.in_node, conn.out_node)

        # Input to input, output to output, and self to self connections
        conns = [(0, 1), (3, 2), (5, 5)]
        for n1, n2 in conns:
            with self.assertRaises(AssertionError, msg=msg):
                g.add_connection(n1, n2)
예제 #11
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    def test_forward(self):
        error_margin = 0.000000000001

        g = Genome(2, 2)
        x = np.array([0.5, 0.5])

        msg = 'Invalid genome output!'

        # No connections
        y = g(x)
        self.assertEqual(y[0], 0.0, msg=msg)
        self.assertEqual(y[1], 0.0, msg=msg)

        # No hidden nodes, modified sigmoid activation
        g.add_connection(0, 2, weight=-0.7)
        g.add_connection(0, 3, weight=-0.1)
        g.add_connection(1, 2, weight=0.5)
        g.add_connection(1, 3, weight=0.9)
        y = g(x)
        self.assertAlmostEqual(y[0],
                               0.3798935676569099,
                               msg=msg,
                               delta=error_margin)
        self.assertAlmostEqual(y[1],
                               0.8765329524347759,
                               msg=msg,
                               delta=error_margin)

        # Different activation
        for n in g.get_nodes():
            if n.type != 'input':
                g.set_activation(n.id, activations.absolute)
        y = g(x)
        self.assertAlmostEqual(y[0], 0.1, msg=msg, delta=error_margin)
        self.assertAlmostEqual(y[1], 0.4, msg=msg, delta=error_margin)

        # With hidden nodes and different activations (sigmoid for the new ones)
        g.add_node(0, activation=activations.sigmoid)
        g.add_node(2, activation=activations.sigmoid)
        g.add_connection(4, 5, 0.5)
        y = g(x)
        self.assertAlmostEqual(y[0],
                               0.08953579350695234,
                               msg=msg,
                               delta=error_margin)
        self.assertAlmostEqual(y[1], 0.4, msg=msg, delta=error_margin)

        # Test with many hidden nodes in a line
        g2 = Genome(2, 2)
        g2.add_connection(0, 2, -0.3)
        g2.add_node(0)
        g2.add_node(2)
        g2.add_node(4)
        g2.add_node(6)
        g2.add_connection(1, 7, 0.7)
        g2.add_connection(4, 3, -0.2)
        y = g2(x)
        self.assertAlmostEqual(y[0],
                               0.18866305913528142,
                               msg=msg,
                               delta=error_margin)
        self.assertAlmostEqual(y[1],
                               0.2743863603871294,
                               msg=msg,
                               delta=error_margin)

        # Test with recursive loop
        g3 = Genome(1, 1)
        x = np.array([0.5])
        g3.add_connection(0, 1, 0.5)
        g3.add_node(0)
        g3.add_node(0)
        g3.add_node(1)
        g3.add_connection(3, 2, 0.5)
        g3.add_connection(4, 3, 0.5)
        y = g3(x)
        self.assertAlmostEqual(y[0],
                               0.9907948306148218,
                               msg=msg,
                               delta=error_margin)
예제 #12
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    def test_kill_percentage(self):
        e = Ecosystem(dc=1.0, ec=1.0, wc=0.4)

        # Create genomes
        g = Genome(2, 2, ecosystem=e)
        g2 = Genome(2, 2, ecosystem=e)
        g3 = Genome(2, 2, ecosystem=e)

        # Add connections and/or nodes
        g.add_connection(0, 2, weight=1.0)
        g.add_connection(0, 3, weight=1.0)
        g.add_connection(1, 2, weight=1.0)

        g2.add_connection(0, 2, weight=0.9)
        g2.add_connection(0, 3, weight=1.0)
        g2.add_connection(1, 2, weight=1.0)
        g2.add_connection(1, 3, weight=1.0)

        g3.add_connection(0, 2, weight=0.1)
        g3.add_connection(0, 3, weight=1.0)
        g3.add_connection(1, 2, weight=1.0)
        g3.add_connection(1, 3, weight=1.0)
        g3.add_node(0)
        g3.add_node(1)
        g3.add_node(2)
        g3.add_connection(0, 6, weight=1.0)
        g3.add_connection(1, 5, weight=1.0)

        g.add_node(1)

        # Test to make sure the correct amount are killed
        msg = 'Incorrect percentage killed!'
        for i in range(10):
            g_copy = g.copy()
            g2_copy = g2.copy()
            g3_copy = g3.copy()

            g_copy.fitness = random.randrange(0, 200)
            g2_copy.fitness = random.randrange(0, 200)
            g3_copy.fitness = random.randrange(0, 200)

            e.add_genome(g_copy)
            e.add_genome(g2_copy)
            e.add_genome(g3_copy)

        e.kill_percentage(50)
        for s in e.species:
            self.assertAlmostEqual(len(s), 5, msg=msg, delta=1)
        self.assertAlmostEqual(len(e.get_population()), 15, msg=msg, delta=1)

        for i in range(5):
            g_copy = g.copy()
            g2_copy = g2.copy()
            g3_copy = g3.copy()

            g_copy.fitness = random.randrange(0, 200)
            g2_copy.fitness = random.randrange(0, 200)
            g3_copy.fitness = random.randrange(0, 200)

            e.add_genome(g_copy)
            e.add_genome(g2_copy)
            e.add_genome(g3_copy)

        e.kill_percentage(25)
        for s in e.species:
            self.assertAlmostEqual(len(s), 8, msg=msg, delta=1)
        self.assertAlmostEqual(len(e.get_population()), 24, msg=msg, delta=1)

        for i in range(2):
            g_copy = g.copy()
            g2_copy = g2.copy()
            g3_copy = g3.copy()

            g_copy.fitness = random.randrange(0, 200)
            g2_copy.fitness = random.randrange(0, 200)
            g3_copy.fitness = random.randrange(0, 200)

            e.add_genome(g_copy)
            e.add_genome(g2_copy)
            e.add_genome(g3_copy)

        e.kill_percentage(75)
        for s in e.species:
            self.assertAlmostEqual(len(s), 3, msg=msg, delta=1)
        self.assertAlmostEqual(len(e.get_population()), 9, msg=msg, delta=1)

        e.kill_percentage(12)
        for s in e.species:
            self.assertAlmostEqual(len(s), 3, msg=msg, delta=1)
        self.assertAlmostEqual(len(e.get_population()), 9, msg=msg, delta=1)

        # Test with a larger population
        e.create_initial_population(100, parent_genome=g)
        e.add_genome(g2.copy())
        e.add_genome(g3.copy())

        e.kill_percentage(90)
        self.assertAlmostEqual(len(e.get_population()), 12, msg=msg, delta=3)
예제 #13
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    def test_get_distance(self):
        error_margin = 0.000000000001

        e = Ecosystem(dc=1.0, ec=1.0, wc=0.4)

        # Create genomes
        g = Genome(2, 2, ecosystem=e)
        g2 = Genome(2, 2, ecosystem=e)
        g3 = Genome(2, 2, ecosystem=e)

        # Add connections and/or nodes
        g.add_connection(0, 2, weight=1.0)
        g.add_connection(0, 3, weight=1.0)
        g.add_connection(1, 2, weight=1.0)

        g2.add_connection(0, 2, weight=0.9)
        g2.add_connection(0, 3, weight=1.0)
        g2.add_connection(1, 2, weight=1.0)
        g2.add_connection(1, 3, weight=1.0)

        g3.add_connection(0, 2, weight=0.1)
        g3.add_connection(0, 3, weight=1.0)
        g3.add_connection(1, 2, weight=1.0)
        g3.add_connection(1, 3, weight=1.0)
        g3.add_node(0)
        g3.add_node(1)
        g3.add_node(2)
        g3.add_connection(0, 6, weight=1.0)
        g3.add_connection(1, 5, weight=1.0)

        g.add_node(1)

        # Test distance results to make sure they are approximately correct
        msg = 'Invalid distance result!'
        self.assertAlmostEqual(e.get_distance(g, g2),
                               0.6133333333333334,
                               msg=msg,
                               delta=error_margin)
        self.assertAlmostEqual(e.get_distance(g2, g),
                               0.6133333333333334,
                               msg=msg,
                               delta=error_margin)
        self.assertAlmostEqual(e.get_distance(g, g3),
                               0.84,
                               msg=msg,
                               delta=error_margin)
        self.assertAlmostEqual(e.get_distance(g3, g),
                               0.84,
                               msg=msg,
                               delta=error_margin)
        self.assertAlmostEqual(e.get_distance(g2, g3),
                               0.7466666666666666,
                               msg=msg,
                               delta=error_margin)
        self.assertAlmostEqual(e.get_distance(g3, g2),
                               0.7466666666666666,
                               msg=msg,
                               delta=error_margin)

        # Test to make sure the same genome returns zero when tested against node_to_itself
        msg = 'Distance between same genomes is not zero!'
        self.assertEqual(e.get_distance(g, g), 0.0, msg)
        self.assertEqual(e.get_distance(g2, g2), 0.0, msg)
        self.assertEqual(e.get_distance(g3, g3), 0.0, msg)
예제 #14
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    def test_cross(self):
        e = Ecosystem()

        # Create genomes
        g = Genome(2, 2, ecosystem=e)
        g2 = Genome(2, 2, ecosystem=e)

        # Cross the genomes
        child = e.cross(g, g2)

        # Test child connections
        msg = 'Child connection doesn\'t exist within either parent!'
        for c in child.get_connections():
            self.assertTrue(
                g.get_connection(c.innovation_number) is not None
                or g2.get_connection(c.innovation_number) is not None, msg)

        # Test to make sure the child has the same amount of connections as the fitter parent
        msg = 'Child missing fitter parent connection(s)!'
        self.assertEqual(len(child.get_connections()),
                         len(g.get_connections()), msg)

        # Test child nodes
        msg = 'Child node doesn\'t exist within either parent!'
        for n in child.get_nodes():
            self.assertTrue(
                g.get_node(n.id) is not None or g2.get_node(n.id) is not None,
                msg)

        # Test to make sure the child has the same amount of nodes as the fitter parent
        msg = 'Child is missing fitter parent node(s)!'
        self.assertEqual(len(child.get_nodes()), len(g.get_nodes()), msg)

        # Test preference for fit parents
        msg = 'Child connection preferred less fit parent!'
        for c in child.get_connections():
            in_both = g.get_connection(
                c.innovation_number) is not None and g2.get_connection(
                    c.innovation_number) is not None
            in_fit_parent = g.get_connection(
                c.innovation_number) is not None and g2.get_connection(
                    c.innovation_number) is None
            self.assertTrue(in_both or in_fit_parent, msg)

        # Add connections and nodes
        g.add_connection(0, 2)
        g.add_connection(0, 3)
        g.add_connection(1, 2)
        g.add_connection(1, 3)
        g.add_node(0)
        g.get_connections()[5].weight = 0.4

        g2.add_connection(0, 2)
        g2.add_connection(0, 3)
        g2.add_connection(1, 2)
        g2.add_connection(1, 3)
        g2.add_node(1)

        g.add_node(2)

        # Assign fitness to genomes
        g.fitness = 10
        g2.fitness = 5

        # Cross the genomes
        child = e.cross(g, g2)

        # Test child connections
        msg = 'Child connection doesn\'t exist within either parent!'
        for c in child.get_connections():
            self.assertTrue(
                g.get_connection(c.innovation_number) is not None
                or g2.get_connection(c.innovation_number) is not None, msg)

        # Test to make sure the child has the same amount of connections as the fitter parent
        msg = 'Child missing fitter parent connection(s)!'
        self.assertEqual(len(child.get_connections()),
                         len(g.get_connections()), msg)

        # Test child nodes
        msg = 'Child node doesn\'t exist within either parent!'
        for n in child.get_nodes():
            self.assertTrue(
                g.get_node(n.id) is not None or g2.get_node(n.id) is not None,
                msg)

        # Test to make sure the child has the same amount of nodes as the fitter parent
        msg = 'Child is missing fitter parent node(s)!'
        self.assertEqual(len(child.get_nodes()), len(g.get_nodes()), msg)

        # Test preference for fit parents
        msg = 'Child connection preferred less fit parent!'
        for c in child.get_connections():
            in_both = g.get_connection(
                c.innovation_number) is not None and g2.get_connection(
                    c.innovation_number) is not None
            in_fit_parent = g.get_connection(
                c.innovation_number) is not None and g2.get_connection(
                    c.innovation_number) is None
            self.assertTrue(in_both or in_fit_parent, msg)

        # Swap the fitness and test again
        g.fitness = 5
        g2.fitness = 10

        # Cross the genomes
        child = e.cross(g, g2)

        # Test child connections
        msg = 'Child connection doesn\'t exist within either parent!'
        for c in child.get_connections():
            self.assertTrue(
                g.get_connection(c.innovation_number) is not None
                or g2.get_connection(c.innovation_number) is not None, msg)

        # Test to make sure the child has the same amount of connections as the fitter parent
        msg = 'Child missing fitter parent connection(s)!'
        self.assertEqual(len(child.get_connections()),
                         len(g2.get_connections()), msg)

        # Test child nodes
        msg = 'Child node doesn\'t exist within either parent!'
        for n in child.get_nodes():
            self.assertTrue(
                g.get_node(n.id) is not None or g2.get_node(n.id) is not None,
                msg)

        # Test to make sure the child has the same amount of nodes as the fitter parent
        msg = 'Child is missing fitter parent node(s)!'
        self.assertEqual(len(child.get_nodes()), len(g2.get_nodes()), msg)

        # Test preference for fit parents
        msg = 'Child connection preferred less fit parent!'
        for c in child.get_connections():
            in_both = g.get_connection(
                c.innovation_number) is not None and g2.get_connection(
                    c.innovation_number) is not None
            in_fit_parent = g.get_connection(
                c.innovation_number) is None and g2.get_connection(
                    c.innovation_number) is not None
            self.assertTrue(in_both or in_fit_parent, msg)