def mutate_gene(self, genome, p_add, p_delete):
"""
Mutate only a single gene.
"""
if p_add < 0 or p_delete < 0:
raise Exception("Mutation parameters must not be negative.")
if p_add + p_delete > 1:
raise Exception("Sum of the mutation probabilities must be less than 1.")
mutated_individual = BehaviorTreeStringRepresentation([])
max_attempts = 100
attempts = 0
while (not mutated_individual.is_valid() or mutated_individual.bt == genome) and attempts < max_attempts:
mutated_individual.set(genome)
index = random.randint(0, len(genome) - 1)
mutation = random.random()
if mutation < p_delete:
mutated_individual.delete_node(index)
elif mutation < p_delete + p_add:
mutated_individual.add_node(index)
else:
mutated_individual.change_node(index)
mutated_individual.close()
mutated_individual.trim()
attempts += 1
if attempts >= max_attempts and (not mutated_individual.is_valid() or mutated_individual.bt == genome):
mutated_individual = BehaviorTreeStringRepresentation([])
return mutated_individual.bt
def test_swap_subtrees(self):
btsr_1 = BehaviorTreeStringRepresentation(
['s(', 'a0', 'f(', 'a0', 'a0', ')', 'a0', ')'])
btsr_2 = BehaviorTreeStringRepresentation(
['s(', 'a0', 'f(', 'a0', 'a0', ')', 's(', 'a0', 'a0', ')', ')'])
btsr_1.swap_subtrees(btsr_2, 6, 6)
self.assertEqual(
btsr_1.bt,
['s(', 'a0', 'f(', 'a0', 'a0', ')', 's(', 'a0', 'a0', ')', ')'])
self.assertEqual(btsr_2.bt,
['s(', 'a0', 'f(', 'a0', 'a0', ')', 'a0', ')'])
# Invalid subtree because it's an up node, no swap
btsr_1.set(['s(', 'a0', 'f(', 'a0', 'a0', ')', 'a0', ')'])
btsr_2.set(
['s(', 'a0', 'f(', 'a0', 'a0', ')', 's(', 'a0', 'a0', ')', ')'])
btsr_1.swap_subtrees(btsr_2, 5, 6)
self.assertEqual(btsr_1.bt,
['s(', 'a0', 'f(', 'a0', 'a0', ')', 'a0', ')'])
self.assertEqual(
btsr_2.bt,
['s(', 'a0', 'f(', 'a0', 'a0', ')', 's(', 'a0', 'a0', ')', ')'])
def test_depth(self):
""" Tests bt_depth function """
btsr = BehaviorTreeStringRepresentation([])
# Normal correct tree
btsr.set(['s(', 'a0', 'f(', 'a0', 'a0', ')', 'a0', ')'])
self.assertEqual(btsr.depth(), 2)
# Goes to 0 before last node - invalid
btsr.set(
['s(', 'a0', 'f(', 'a0', 'a0', ')', 'a0', ')', 's(', 'a0', ')'])
self.assertEqual(btsr.depth(), -1)
# Goes to 0 before last node - invalid
btsr.set(['s(', 'a0', 'f(', 'a0', 'a0', ')', ')', 'a0', ')'])
self.assertEqual(btsr.depth(), -1)
# Goes to 0 before last node - invalid
btsr.set(['s(', 'a0', 'f(', 'a0', 'a0', ')', 'a0'])
self.assertEqual(btsr.depth(), -1)
# Just an action node - no depth
btsr.set(['a0'])
self.assertEqual(btsr.depth(), 0)
def test_trim(self):
""" Tests trim function """
btsr = BehaviorTreeStringRepresentation([])
btsr.set(
['s(', 'a0', 'f(', 'a0', 'a0', ')', 'a0', 's(', 'a0', ')', ')'])
btsr.trim()
self.assertEqual(btsr.bt,
['s(', 'a0', 'f(', 'a0', 'a0', ')', 'a0', 'a0', ')'])
btsr.set(['s(', 'a0', 'f(', ')', 'a0', 's(', 'a0', ')', ')'])
btsr.trim()
self.assertEqual(btsr.bt, ['s(', 'a0', 'a0', 'a0', ')'])
btsr.set(
['s(', 'a0', 'f(', 'a1', 's(', 'a2', ')', 'a3', ')', 'a4', ')'])
btsr.trim()
self.assertEqual(btsr.bt,
['s(', 'a0', 'f(', 'a1', 'a2', 'a3', ')', 'a4', ')'])
btsr.set(['s(', 'a0', 'f(', 's(', 'a2', 'a3', ')', ')', 'a4', ')'])
btsr.trim()
self.assertEqual(btsr.bt, ['s(', 'a0', 'a2', 'a3', 'a4', ')'])
btsr.set(['s(', 'a0', ')'])
btsr.trim()
self.assertEqual(btsr.bt, ['s(', 'a0', ')'])
def test_close(self):
""" Tests close function """
btsr = BehaviorTreeStringRepresentation([])
btsr.close()
self.assertEqual(btsr.bt, [])
# Correct tree with just one action
btsr.set(['a0']).close()
self.assertEqual(btsr.bt, ['a0'])
# Correct tree
btsr.set(['s(', 's(', 'a0', ')', ')']).close()
self.assertEqual(btsr.bt, ['s(', 's(', 'a0', ')', ')'])
# Missing up at end
btsr.set(['s(', 's(', 'a0', ')', 's(', 'a0', 's(', 'a0']).close()
self.assertEqual(
btsr.bt,
['s(', 's(', 'a0', ')', 's(', 'a0', 's(', 'a0', ')', ')', ')'])
# Too many up at end
btsr.set(['s(', 'a0', ')', ')', ')']).close()
self.assertEqual(btsr.bt, ['s(', 'a0', ')'])
# Too many up but not at the end
btsr.set(['s(', 's(', 'a0', ')', ')', ')', 'a1', ')']).close()
self.assertEqual(btsr.bt, ['s(', 's(', 'a0', ')', 'a1', ')'])
def test_mutate_gene(self):
gp_operators = Operators()
genome = ['s(', 'c0', ')']
with self.assertRaises(Exception):
gp_operators.mutate_gene(genome, p_add=-1, p_delete=1)
with self.assertRaises(Exception):
gp_operators.mutate_gene(genome, p_add=1, p_delete=1)
for _ in range(10):
mutated_genome = gp_operators.mutate_gene(genome,
p_add=1,
p_delete=0)
self.assertGreaterEqual(len(mutated_genome), len(genome))
mutated_genome = gp_operators.mutate_gene(genome,
p_add=0,
p_delete=1)
self.assertLessEqual(len(mutated_genome), len(genome))
mutated_genome = gp_operators.mutate_gene(genome,
p_add=0,
p_delete=0)
btsr = BehaviorTreeStringRepresentation(mutated_genome)
self.assertNotEqual(mutated_genome, genome)
self.assertTrue(btsr.is_valid())
mutated_genome = gp_operators.mutate_gene(genome,
p_add=0.3,
p_delete=0.3)
btsr.set(mutated_genome)
self.assertNotEqual(mutated_genome, genome)
self.assertTrue(btsr.is_valid())
def test_crossover_genome(self):
gp_operators = Operators()
genome1 = ['s(', 'c0', 'f(', 'c0', 'a0', ')', 'a0', ')']
genome2 = ['f(', 'c1', 's(', 'c1', 'a1', ')', 'a1', ')']
offspring1, offspring2 = gp_operators.crossover_genome(genome1,
genome2,
replace=True)
self.assertNotEqual(offspring1, [])
self.assertNotEqual(offspring2, [])
self.assertNotEqual(offspring1, genome1)
self.assertNotEqual(offspring1, genome2)
self.assertNotEqual(offspring2, genome1)
self.assertNotEqual(offspring2, genome2)
btsr_1 = BehaviorTreeStringRepresentation(offspring1)
self.assertTrue(btsr_1.is_valid())
btsr_1 = btsr_1.set(offspring2)
self.assertTrue(btsr_1.is_valid())
genome1 = ['a0']
genome2 = ['a1']
offspring1, offspring2 = gp_operators.crossover_genome(genome1,
genome2,
replace=True)
self.assertEqual(offspring1, genome2)
self.assertEqual(offspring2, genome1)
genome1 = []
offspring1, offspring2 = gp_operators.crossover_genome(genome1,
genome2,
replace=True)
self.assertEqual(offspring1, [])
self.assertEqual(offspring2, [])
for i in range(10):
random.seed(i)
offspring1, offspring2 = gp_operators.crossover_genome(
gp_operators.random_genome(10),
gp_operators.random_genome(10),
replace=True)
btsr_1 = btsr_1.set(offspring1)
self.assertTrue(btsr_1.is_valid())
btsr_1 = btsr_1.set(offspring2)
self.assertTrue(btsr_1.is_valid())
genome1 = ['s(', 'f(', 'c0', 'a0', ')', 'a0', ')']
genome2 = ['f(', 's(', 'c1', 'a1', ')', 'a1', ')']
offspring1, offspring2 = gp_operators.crossover_genome(genome1,
genome2,
replace=False)
self.assertNotEqual(offspring1, genome1)
self.assertNotEqual(offspring2, genome2)
for gene in genome1:
self.assertTrue(gene in offspring1)
for gene in genome2:
self.assertTrue(gene in offspring2)
def test_find_children(self):
""" Tests find_children function """
btsr = BehaviorTreeStringRepresentation([])
btsr.set(['s(', 'a0', 'f(', 'a0', ')', 'a0', ')'])
self.assertEqual(btsr.find_children(0), [1, 2, 5])
self.assertEqual(btsr.find_children(1), [])
self.assertEqual(btsr.find_children(2), [3])
self.assertEqual(btsr.find_children(3), [])
self.assertEqual(btsr.find_children(4), [])
self.assertEqual(btsr.find_children(5), [])
def test_find_parent(self):
""" Tests find_parent function """
btsr = BehaviorTreeStringRepresentation([])
btsr.set(['s(', 'a0', 'f(', 'a0', ')', 'a0', ')'])
self.assertEqual(btsr.find_parent(0), None)
self.assertEqual(btsr.find_parent(1), 0)
self.assertEqual(btsr.find_parent(2), 0)
self.assertEqual(btsr.find_parent(3), 2)
self.assertEqual(btsr.find_parent(4), 2)
self.assertEqual(btsr.find_parent(5), 0)
def crossover_genome(self, genome1, genome2, replace):
"""
Do crossover between genomes at random points
"""
bt1 = BehaviorTreeStringRepresentation(genome1)
bt2 = BehaviorTreeStringRepresentation(genome2)
offspring1 = BehaviorTreeStringRepresentation([])
offspring2 = BehaviorTreeStringRepresentation([])
if bt1.is_valid() and bt2.is_valid():
max_attempts = 100
attempts = 0
found = False
while not found and attempts < max_attempts:
offspring1.set(bt1.bt)
offspring2.set(bt2.bt)
cop1 = -1
cop2 = -1
if len(genome1) == 1:
cop1 = 0 # Change whole tree
else:
while not offspring1.is_subtree(cop1):
cop1 = random.randint(1, len(genome1) - 1)
if len(genome2) == 1:
cop2 = 0 # Change whole tree
else:
while not offspring2.is_subtree(cop2):
cop2 = random.randint(1, len(genome2) - 1)
if replace:
offspring1.swap_subtrees(offspring2, cop1, cop2)
else:
subtree1 = offspring1.get_subtree(cop1)
subtree2 = offspring2.get_subtree(cop2)
if len(genome1) == 1:
index1 = random.randint(0, 1)
else:
index1 = random.randint(1, len(genome1) - 1)
if len(genome2) == 1:
index2 = random.randint(0, 1)
else:
index2 = random.randint(1, len(genome2) - 1)
offspring1.insert_subtree(subtree2, index1)
offspring2.insert_subtree(subtree1, index2)
attempts += 1
if offspring1.is_valid() and offspring2.is_valid():
found = True
if not found:
offspring1.set([])
offspring2.set([])
return offspring1.bt, offspring2.bt
def test_get_subtree(self):
""" Tests get_subtree function """
btsr = BehaviorTreeStringRepresentation(
['s(', 'a0', 'f(', 'a0', 'a0', ')', 'a0', ')'])
subtree = btsr.get_subtree(1)
self.assertEqual(subtree, ['a0'])
btsr.set(
['s(', 'a0', 'f(', 'a0', 'a0', ')', 's(', 'a0', 'a0', ')', ')'])
subtree = btsr.get_subtree(6)
self.assertEqual(subtree, ['s(', 'a0', 'a0', ')'])
btsr.set(['s(', 'a0', 'f(', 'a0', 'a0', ')', ')'])
subtree = btsr.get_subtree(2)
self.assertEqual(subtree, ['f(', 'a0', 'a0', ')'])
subtree = btsr.get_subtree(5)
self.assertEqual(subtree, [])
def test_length(self):
""" Tests bt_length function """
btsr = BehaviorTreeStringRepresentation([])
btsr.set(['s(', 'a0', 'a1', ')'])
self.assertEqual(btsr.length(), 3)
btsr.set(['s(', 'a0', 'f(', 'a0', 'a0', ')', 'a0', ')'])
self.assertEqual(btsr.length(), 6)
btsr.set(['s(', ')'])
self.assertEqual(btsr.length(), 1)
btsr.set(['a0'])
self.assertEqual(btsr.length(), 1)
def test_delete_node(self):
""" Tests delete_node function """
btsr = BehaviorTreeStringRepresentation([])
btsr.set(['s(', 'a0', 'f(', 'a0', 'a0', ')', 'a0', ')']).delete_node(0)
self.assertEqual(btsr.bt, [])
btsr.set(['s(', 'a0', 'f(', 'a0', 'a0', ')', 's(', 'a0', ')',
')']).delete_node(0)
self.assertEqual(btsr.bt, [])
btsr.set([
's(', 'a0', 'f(', 'a0', 's(', 'a0', ')', ')', 's(', 'a0', ')', ')'
]).delete_node(0)
self.assertEqual(btsr.bt, [])
btsr.set(['s(', 'a0', 'f(', 'a0', 'a0', ')', 'a0', ')']).delete_node(1)
self.assertEqual(btsr.bt, ['s(', 'f(', 'a0', 'a0', ')', 'a0', ')'])
btsr.set(['s(', 'a0', 'f(', 'a1', 'a2', ')', 'a3', ')']).delete_node(2)
self.assertEqual(btsr.bt, ['s(', 'a0', 'a3', ')'])
btsr.set(['s(', 'a0', 'f(', 'a0', ')', 'a0', ')']).delete_node(3)
self.assertEqual(btsr.bt, ['s(', 'a0', 'f(', ')', 'a0', ')'])
btsr.set(['s(', 'a0', ')']).delete_node(2)
self.assertEqual(btsr.bt, ['s(', 'a0', ')'])
def test_change_node(self):
""" Tests change_node function """
btsr = BehaviorTreeStringRepresentation([])
random.seed(1337)
# No new node given, change to random node
btsr.set(['s(', 'a0', 'a0', ')']).change_node(2)
self.assertNotEqual(btsr.bt[2], 'a0')
# Change control node to action node
btsr.set(['s(', 'a0', 'f(', 'a0', 'a0', ')', 'a0',
')']).change_node(2, 'a0')
self.assertEqual(btsr.bt, ['s(', 'a0', 'a0', 'a0', ')'])
# Change control node to action node - correct up must be removed too
btsr.set(['s(', 'a0', 'f(', 's(', 'a0', ')', 'a0', ')', 'a0',
')']).change_node(2, 'a0')
self.assertEqual(btsr.bt, ['s(', 'a0', 'a0', 'a0', ')'])
btsr.set(['s(', 'a0', 'f(', 's(', 'a0', ')', 'a1', ')', 'a0',
')']).change_node(3, 'a0')
self.assertEqual(btsr.bt,
['s(', 'a0', 'f(', 'a0', 'a1', ')', 'a0', ')'])
# Change action node to control node
btsr.set(['s(', 'a0', 'a0', ')']).change_node(1, 'f(')
self.assertEqual(btsr.bt, ['s(', 'f(', 'a0', 'a0', ')', 'a0', ')'])
# Change action node to action node
btsr.set(['s(', 'a0', 'a0', ')']).change_node(1, 'a1')
self.assertEqual(btsr.bt, ['s(', 'a1', 'a0', ')'])
# Change control node to control node
btsr.set(['s(', 'a0', 'a0', ')']).change_node(0, 'f(')
self.assertEqual(btsr.bt, ['f(', 'a0', 'a0', ')'])
# Change up node, not possible
btsr.set(['s(', 'a0', 'f(', 'a0', 'a0', ')', 'a0',
')']).change_node(5, 'a0')
self.assertEqual(btsr.bt,
['s(', 'a0', 'f(', 'a0', 'a0', ')', 'a0', ')'])
def test_find_up_node(self):
""" Tests find_up_node function """
btsr = BehaviorTreeStringRepresentation([])
btsr.set(['s(', 'a0', 'f(', 'a0', ')', 'a0', ')'])
self.assertEqual(btsr.find_up_node(0), 6)
btsr.set(['s(', 'a0', 'f(', 'a0', ')', 'a0', ')'])
self.assertEqual(btsr.find_up_node(2), 4)
btsr.set(['s(', 'a0', 'f(', 's(', 'a0', ')', 'a0', ')'])
self.assertEqual(btsr.find_up_node(2), 7)
btsr.set(['s(', 'a0', 'f(', 'a0', ')', 'a0', ')'])
with self.assertRaises(Exception):
_ = btsr.find_up_node(1)
btsr.set(['s(', 'a0', 'f(', 'a0', ')', 'a0'])
with self.assertRaises(Exception):
_ = btsr.find_up_node(0)
btsr.set(['s(', 's(', 'a0', 'f(', 'a0', ')', 'a0'])
with self.assertRaises(Exception):
_ = btsr.find_up_node(1)
def test_add_node(self):
""" Tests add_node function """
btsr = BehaviorTreeStringRepresentation([])
random.seed(1337)
btsr.set(['a0']).add_node(0, 's(')
self.assertEqual(btsr.bt, ['s(', 'a0', ')'])
btsr.set(['s(', 'a0', 'a0', ')']).add_node(2)
self.assertEqual(btsr.bt, ['s(', 'a0', 'a3', 'a0', ')'])
btsr.set(['s(', 'a0', 'f(', 'a0', 'a0', ')', 'a0',
')']).add_node(2, 'a0')
self.assertEqual(btsr.bt,
['s(', 'a0', 'a0', 'f(', 'a0', 'a0', ')', 'a0', ')'])
btsr.set(['s(', 'a0', 'f(', 'a0', 'a0', ')', 'a0',
')']).add_node(3, 'a0')
self.assertEqual(btsr.bt,
['s(', 'a0', 'f(', 'a0', 'a0', 'a0', ')', 'a0', ')'])
btsr.set(['s(', 'a0', 'f(', 'a0', 'a0', ')', 'a0',
')']).add_node(0, 'f(')
self.assertEqual(
btsr.bt, ['f(', 's(', 'a0', 'f(', 'a0', 'a0', ')', 'a0', ')', ')'])
btsr.set(['s(', 'a0', 'f(', 'a0', 'a0', ')', 'a0',
')']).add_node(4, 's(')
self.assertTrue(btsr.is_valid())
btsr.set(['s(', 'a0', 'f(', 'a0', 'a0', ')', 'a0',
')']).add_node(2, 'f(')
self.assertTrue(btsr.is_valid())
btsr.set(['s(', 'a0', 'f(', 'a0', 'a0', ')', 'a0',
')']).add_node(1, 'f(')
self.assertTrue(btsr.is_valid())
btsr.set(['s(', 'a0', 'f(', 'c1', 'a0', ')', ')']).add_node(2, 'f(')
self.assertTrue(btsr.is_valid())
def test_is_valid(self):
btsr = BehaviorTreeStringRepresentation([])
self.assertFalse(btsr.is_valid())
# Valid tree
btsr.set(['s(', 'c0', 'f(', 'c0', 'a0', ')', 'a0', ')'])
self.assertTrue(btsr.is_valid())
# Minimal valid tree - just an action node
btsr.set(['a0'])
self.assertTrue(btsr.is_valid())
# Two control nodes at root level - not valid
btsr.set(
['s(', 'c0', 'f(', 'c0', 'a0', ')', 'a0', ')', 's(', 'a0', ')'])
self.assertFalse(btsr.is_valid())
# Action node at root level - not valid
btsr.set(['s(', 'c0', 'f(', 'c0', 'a0', ')', ')', 'a0', ')'])
self.assertFalse(btsr.is_valid())
# Too few up nodes - not valid
btsr.set(['s(', 'c0', 'f(', 'c0', 'a0', ')', 'a0'])
self.assertFalse(btsr.is_valid())
# Too few up nodes - not valid
btsr.set(['s(', 'c0', 'f(', 'c0', 'a0', ')'])
self.assertFalse(btsr.is_valid())
# No control nodes, but more than one action - not valid
btsr.set(['a0', 'a0'])
self.assertFalse(btsr.is_valid())
# Starts with an up node - not valid
btsr.set([')', 'f(', 'c0', 'a0', ')'])
self.assertFalse(btsr.is_valid())
# Just a control node - not valid
btsr.set(['s(', ')'])
self.assertFalse(btsr.is_valid())
# Just a control node - not valid
btsr.set(['s(', 's('])
self.assertFalse(btsr.is_valid())
# Up just after control node
btsr.set(['s(', 'f(', ')', 'a0', ')'])
self.assertFalse(btsr.is_valid())
# Unknown characters
btsr.set(['s(', 'c0', 'x', 'y', 'z', ')'])
self.assertFalse(btsr.is_valid())