def test_fittest():
ref = B.tensor([2, 0, 1, 1, 0, 2, 1, 1])
d = B.tensor([2, 1, 1, 0, 1, 1, 1, 1])
pop = B.tensor([ref, d, ref, d, ref, d])
fitness_function = InvertedCosineSimilarity(ref)
selector = SelectFittest()
selected_pop, fitness_scores = selector(fitness_function, pop, pop)
print(selected_pop)
assert selected_pop.shape == pop.shape
for chromosome in selected_pop:
assert B.tensor_equal(chromosome, ref)
def test_cosine_similarity_1dpopulation(backends):
"test the function works on a population and broadcast correctly"
reference = [1, 0, 1, 1, 0, 1, 1, 1]
different = [1, 1, 1, 0, 1, 1, 1, 1]
r = B.tensor(reference)
d = B.tensor(different)
population = B.tensor([r, d, r])
cs = InvertedCosineSimilarity(r)
# similar vector have a distance of 1
distances = cs(population)
print("distances", distances)
assert int(distances[0]) == 1
assert distances[1] < 1
assert int(distances[2]) == 1
def _flatten_population(self, population):
"""Convert the population to a 1D array as many ops (e.g norm) don't
work on Ndimension
"""
if len(population.shape) < 3:
return population
num_chromosomes = population.shape[0]
flattened_size = int(B.prod(B.tensor(population.shape[1:])))
return B.reshape(population, (num_chromosomes, flattened_size))
def assign(self, chromosomes):
"""Assign concrete values to the input
"""
chromosomes = B.tensor(chromosomes)
if chromosomes.shape != self.shape:
raise ValueError(
'Incompatible input shape expected: %s - got: %s' %
(self.shape, chromosomes.shape))
self.chromosomes = chromosomes
def test_sum2d():
t = B.randint(0, 10, (10, 10, 10))
v = Sum().call(t)
result = []
for r in t:
result.append(B.sum(r, axis=-1))
result = B.tensor(result)
assert v.shape == (10, )
for idx, a in enumerate(v):
assert v[idx].all() == result[idx].all()
def __init__(self, max_sum_value=None, **kwargs):
"""Compute the sum of the chromosomes as fitness values.
Args:
expected_max_sum_value (int, optional): What is the maximum value
the sum per chromosome will reach. Used to normalize the fitness
function between 0 and 1 if specified. Defaults to None.
Note:
This fitness function is used to solve the MAXONE problem.
"""
super(Sum, self).__init__('sum_genes', **kwargs)
if max_sum_value:
self.max_sum_value = B.tensor(max_sum_value)
else:
self.max_sum_value = None
def __init__(self, reference_chromosome, **kwargs):
"""Inverted Cosine similarity function that returns 1 when chromosomes
are similar to the reference chromose and [0, 1[ when different
For reference implementation see
https://github.com/scipy/scipy/blob/v0.14.0/scipy/spatial/distance.py#L267 # noqa
Args:
reference_chromosome (tensor1D): reference_chromosome.
"""
super(InvertedCosineSimilarity, self).__init__('invet_cosine_sim',
**kwargs)
# cache ref chromosome flattend
self.ref_chromosome = B.flatten(B.tensor(reference_chromosome))
# caching ref pop norm
self.ref_norm = B.norm(self.ref_chromosome)
def test_helloworld():
"Solve the MAXONE problem"
NUM_EVOLUTIONS = 10
SHAPE = (512, 1024)
MAX_VAL = 1
population = genRandIntPopulation(SHAPE, MAX_VAL)
inputs = Input(SHAPE)
x = RandomMutations1D(max_gene_value=1)(inputs)
outputs = UniformCrossover1D()(x)
gf = GeneFlow(inputs, outputs, debug=0)
fitness_function = Sum(max_sum_value=SHAPE[1])
evolution_strategy = SelectFittest()
gf.compile(evolution_strategy, fitness_function)
gf.summary()
results = gf.evolve(population, num_evolutions=NUM_EVOLUTIONS)
assert results
metrics = results.get_metrics_history()
# check metrics
for metric_name, vals in metrics.items():
assert isinstance(vals, list)
assert len(vals) == 10
assert isinstance(vals[9], float)
assert 'fitness_mean' in metrics
assert 'fitness_max' in metrics
# assert the engine solved the (Trivial) problem
assert max(metrics['fitness_max']) == 1
assert metrics['fitness_max'][9] == 1
assert min(metrics['fitness_max']) < 1 # max sure we did improve
# check population value
population = results.get_populations()
assert (population.shape) == SHAPE
assert B.tensor_equal(population[0], B.tensor([1] * SHAPE[1]))
def test_box_unbox_tensor():
val = tensor([1, 2, 3])
assert unbox(box(val)).all() == val.all()
def test_eager():
"when passing concrete value GF is suppposed to return a concrete value"
val = B.tensor(42)
assert Dummy(debug=True)(val) == val
