def testVars(self):
classification.f1_score(predictions=array_ops.ones((10, 1)),
labels=array_ops.ones((10, 1)),
num_thresholds=3)
expected = {
'f1/true_positives:0', 'f1/false_positives:0',
'f1/false_negatives:0'
}
self.assertEqual(expected,
set(v.name for v in variables.local_variables()))
self.assertEqual(set(expected),
set(v.name for v in variables.local_variables()))
self.assertEqual(
set(expected),
set(v.name
for v in ops.get_collection(ops.GraphKeys.METRIC_VARIABLES)))
def testUpdatesCollection(self):
my_collection_name = '__updates__'
_, f1_op = classification.f1_score(
predictions=array_ops.ones((10, 1)),
labels=array_ops.ones((10, 1)),
num_thresholds=3,
updates_collections=[my_collection_name])
self.assertListEqual(ops.get_collection(my_collection_name), [f1_op])
def testMetricsCollection(self):
my_collection_name = '__metrics__'
f1, _ = classification.f1_score(
predictions=array_ops.ones((10, 1)),
labels=array_ops.ones((10, 1)),
num_thresholds=3,
metrics_collections=[my_collection_name])
self.assertListEqual(ops.get_collection(my_collection_name), [f1])
def testWithMultipleUpdates(self):
num_samples = 1000
batch_size = 10
num_batches = int(num_samples / batch_size)
# Create the labels and data.
labels = np.random.randint(0, 2, size=(num_samples, 1))
noise = np.random.normal(0.0, scale=0.2, size=(num_samples, 1))
predictions = 0.4 + 0.2 * labels + noise
predictions[predictions > 1] = 1
predictions[predictions < 0] = 0
thresholds = [-0.01, 0.5, 1.01]
expected_max_f1 = -1.0
for threshold in thresholds:
tp = 0
fp = 0
fn = 0
tn = 0
for i in range(num_samples):
if predictions[i] >= threshold:
if labels[i] == 1:
tp += 1
else:
fp += 1
else:
if labels[i] == 1:
fn += 1
else:
tn += 1
epsilon = 1e-7
expected_prec = tp / (epsilon + tp + fp)
expected_rec = tp / (epsilon + tp + fn)
expected_f1 = (2 * expected_prec * expected_rec /
(epsilon + expected_prec + expected_rec))
if expected_f1 > expected_max_f1:
expected_max_f1 = expected_f1
labels = labels.astype(np.float32)
predictions = predictions.astype(np.float32)
tf_predictions, tf_labels = tf.data.Dataset.from_tensor_slices(
(predictions, labels
)).repeat().batch(batch_size).make_one_shot_iterator().get_next()
f1, f1_op = classification.f1_score(tf_labels,
tf_predictions,
num_thresholds=3)
with self.cached_session() as sess:
sess.run(variables.local_variables_initializer())
for _ in range(num_batches):
sess.run([f1_op])
# Since this is only approximate, we can't expect a 6 digits match.
# Although with higher number of samples/thresholds we should see the
# accuracy improving
self.assertAlmostEqual(expected_max_f1, f1.eval(), 2)
def testZeroLabelsPredictions(self):
with self.cached_session() as sess:
predictions = array_ops.zeros([4], dtype=dtypes.float32)
labels = array_ops.zeros([4])
f1, f1_op = classification.f1_score(predictions,
labels,
num_thresholds=3)
sess.run(variables.local_variables_initializer())
sess.run([f1_op])
self.assertAlmostEqual(0.0, f1.eval(), places=5)
def testSomeCorrect(self):
predictions = constant_op.constant([1, 0, 1, 0],
shape=(1, 4),
dtype=dtypes.float32)
labels = constant_op.constant([0, 1, 1, 0], shape=(1, 4))
f1, f1_op = classification.f1_score(predictions,
labels,
num_thresholds=1)
with self.cached_session() as sess:
sess.run(variables.local_variables_initializer())
sess.run([f1_op])
# Threshold 0 will have around 0.5 precision and 1 recall yielding an F1
# score of 2 * 0.5 * 1 / (1 + 0.5).
self.assertAlmostEqual(2 * 0.5 * 1 / (1 + 0.5), f1.eval())
def testAllCorrect(self):
inputs = np.random.randint(0, 2, size=(100, 1))
with self.cached_session() as sess:
predictions = constant_op.constant(inputs, dtype=dtypes.float32)
labels = constant_op.constant(inputs)
f1, f1_op = classification.f1_score(predictions,
labels,
num_thresholds=3)
sess.run(variables.local_variables_initializer())
sess.run([f1_op])
self.assertEqual(1, f1.eval())
def testWeights2d(self):
with self.cached_session() as sess:
predictions = constant_op.constant([[1, 0], [1, 0]],
shape=(2, 2),
dtype=dtypes.float32)
labels = constant_op.constant([[0, 1], [1, 0]], shape=(2, 2))
weights = constant_op.constant([[0, 0], [1, 1]],
shape=(2, 2),
dtype=dtypes.float32)
f1, f1_op = classification.f1_score(predictions,
labels,
weights,
num_thresholds=3)
sess.run(variables.local_variables_initializer())
sess.run([f1_op])
self.assertAlmostEqual(1.0, f1.eval(), places=5)
def testAllIncorrect(self):
inputs = np.random.randint(0, 2, size=(10000, 1))
with self.cached_session() as sess:
predictions = constant_op.constant(inputs, dtype=dtypes.float32)
labels = constant_op.constant(1 - inputs, dtype=dtypes.float32)
f1, f1_op = classification.f1_score(predictions,
labels,
num_thresholds=3)
sess.run(variables.local_variables_initializer())
sess.run([f1_op])
# Threshold 0 will have around 0.5 precision and 1 recall yielding an F1
# score of 2 * 0.5 * 1 / (1 + 0.5).
self.assertAlmostEqual(2 * 0.5 * 1 / (1 + 0.5),
f1.eval(),
places=2)
def testValueTensorIsIdempotent(self):
predictions = random_ops.random_uniform((10, 3),
maxval=1,
dtype=dtypes.float32,
seed=1)
labels = random_ops.random_uniform((10, 3),
maxval=2,
dtype=dtypes.int64,
seed=2)
f1, f1_op = classification.f1_score(predictions,
labels,
num_thresholds=3)
with self.cached_session() as sess:
sess.run(variables.local_variables_initializer())
# Run several updates.
for _ in range(10):
sess.run([f1_op])
# Then verify idempotency.
initial_f1 = f1.eval()
for _ in range(10):
self.assertAllClose(initial_f1, f1.eval())