def _mode(self):
mode = (self.a - 1.0) / (self.a_b_sum - 2.0)
if self.allow_nan_stats:
nan = np.array(np.nan, dtype=self.dtype.as_numpy_dtype())
return math_ops.select(
math_ops.logical_and(math_ops.greater(self.a, 1.0), math_ops.greater(self.b, 1.0)),
mode,
array_ops.fill(self.batch_shape(), nan, name="nan"),
)
else:
return control_flow_ops.with_dependencies(
[
check_ops.assert_less(
array_ops.ones((), dtype=self.dtype),
self.a,
message="Mode not defined for components of a <= 1.",
),
check_ops.assert_less(
array_ops.ones((), dtype=self.dtype),
self.b,
message="Mode not defined for components of b <= 1.",
),
],
mode,
)
def mode(self, name="mode"):
"""Mode of the distribution.
Note that the mode for the Beta distribution is only defined
when `a > 1`, `b > 1`. This returns the mode when `a > 1` and `b > 1`,
and NaN otherwise. If `self.allow_nan_stats` is `False`, an exception
will be raised rather than returning `NaN`.
Args:
name: The name for this op.
Returns:
Mode of the Beta distribution.
"""
with ops.name_scope(self.name):
with ops.op_scope([self._a, self._b, self._a_b_sum], name):
a = self._a
b = self._b
a_b_sum = self._a_b_sum
one = constant_op.constant(1, self.dtype)
mode = (a - 1)/ (a_b_sum - 2)
if self.allow_nan_stats:
return math_ops.select(
math_ops.logical_and(
math_ops.greater(a, 1), math_ops.greater(b, 1)),
mode,
(constant_op.constant(float("NaN"), dtype=self.dtype) *
array_ops.ones_like(a_b_sum, dtype=self.dtype)))
else:
return control_flow_ops.with_dependencies([
check_ops.assert_less(one, a),
check_ops.assert_less(one, b)], mode)
def _verify_input(tensor_list, labels, probs_list):
"""Verify that batched inputs are well-formed."""
checked_probs_list = []
for probs in probs_list:
# Since number of classes shouldn't change at runtime, probabilities shape
# should be fully defined.
probs.get_shape().assert_is_fully_defined()
# Probabilities must be 1D.
probs.get_shape().assert_has_rank(1)
# Probabilities must be nonnegative and sum to one.
tol = 1e-6
prob_sum = math_ops.reduce_sum(probs)
checked_probs = control_flow_ops.with_dependencies([
check_ops.assert_non_negative(probs),
check_ops.assert_less(prob_sum, 1.0 + tol),
check_ops.assert_less(1.0 - tol, prob_sum)
], probs)
checked_probs_list.append(checked_probs)
# All probabilities should be the same length.
prob_length = checked_probs_list[0].get_shape().num_elements()
for checked_prob in checked_probs_list:
if checked_prob.get_shape().num_elements() != prob_length:
raise ValueError('Probability parameters must have the same length.')
# Labels tensor should only have batch dimension.
labels.get_shape().assert_has_rank(1)
for tensor in tensor_list:
# Data tensor should have a batch dimension.
shape = tensor.get_shape().with_rank_at_least(1)
# Data and label batch dimensions must be compatible.
tensor_shape.dimension_at_index(shape, 0).assert_is_compatible_with(
labels.get_shape()[0])
# Data and labels must have the same, strictly positive batch size. Since we
# can't assume we know the batch size at graph creation, add runtime checks.
labels_batch_size = array_ops.shape(labels)[0]
lbl_assert = check_ops.assert_positive(labels_batch_size)
# Make each tensor depend on its own checks.
labels = control_flow_ops.with_dependencies([lbl_assert], labels)
tensor_list = [
control_flow_ops.with_dependencies([
lbl_assert,
check_ops.assert_equal(array_ops.shape(x)[0], labels_batch_size)
], x) for x in tensor_list
]
# Label's classes must be integers 0 <= x < num_classes.
labels = control_flow_ops.with_dependencies([
check_ops.assert_integer(labels), check_ops.assert_non_negative(labels),
check_ops.assert_less(labels, math_ops.cast(prob_length, labels.dtype))
], labels)
return tensor_list, labels, checked_probs_list
def test_doesnt_raise_when_less_and_broadcastable_shapes(self):
with self.test_session():
small = constant_op.constant([1], name="small")
big = constant_op.constant([3, 2], name="big")
with ops.control_dependencies([check_ops.assert_less(small, big)]):
out = array_ops.identity(small)
out.eval()
def _entropy(self):
probs = self._probs
if self.validate_args:
probs = control_flow_ops.with_dependencies(
[check_ops.assert_less(
probs,
constant_op.constant(1., probs.dtype),
message="Entropy is undefined when logits = inf or probs = 1.")],
probs)
# Claim: entropy(p) = softplus(s)/p - s
# where s=logits and p=probs.
#
# Proof:
#
# entropy(p)
# := -[(1-p)log(1-p) + plog(p)]/p
# = -[log(1-p) + plog(p/(1-p))]/p
# = -[-softplus(s) + ps]/p
# = softplus(s)/p - s
#
# since,
# log[1-sigmoid(s)]
# = log[1/(1+exp(s)]
# = -log[1+exp(s)]
# = -softplus(s)
#
# using the fact that,
# 1-sigmoid(s) = sigmoid(-s) = 1/(1+exp(s))
return nn.softplus(self.logits) / probs - self.logits
def _variance(self):
var = self._ones() * math_ops.square(self.sigma) * self.df / (self.df - 2)
# When 1 < df <= 2, variance is infinite.
inf = np.array(np.inf, dtype=self.dtype.as_numpy_dtype())
result_where_defined = math_ops.select(
math_ops.greater(self.df, array_ops.fill(self.batch_shape(), 2.0)),
var,
array_ops.fill(self.batch_shape(), inf, name="inf"),
)
if self.allow_nan_stats:
nan = np.array(np.nan, dtype=self.dtype.as_numpy_dtype())
return math_ops.select(
math_ops.greater(self.df, self._ones()),
result_where_defined,
array_ops.fill(self.batch_shape(), nan, name="nan"),
)
else:
return control_flow_ops.with_dependencies(
[
check_ops.assert_less(
array_ops.ones((), dtype=self.dtype),
self.df,
message="variance not defined for components of df <= 1",
)
],
result_where_defined,
)
def variance(self, name="variance"):
"""Variance of each batch member.
Variance for inverse gamma is defined only for `alpha > 2`. If
`self.strict_statistics` is `True`, an exception will be raised rather
than returning `NaN`.
Args:
name: A name to give this op.
Returns:
The variance for every batch member, a `Tensor` with same `dtype` as self.
"""
alpha = self._alpha
beta = self._beta
with ops.name_scope(self.name):
with ops.op_scope([alpha, beta], name):
var_if_defined = math_ops.square(self._beta) / (
math_ops.square(self._alpha - 1.0) * (self._alpha - 2.0)
)
if self.strict_statistics:
two = ops.convert_to_tensor(2.0, dtype=self.dtype)
return control_flow_ops.with_dependencies([check_ops.assert_less(two, alpha)], var_if_defined)
else:
alpha_gt_2 = alpha > 2.0
nan = np.nan * self._ones()
return math_ops.select(alpha_gt_2, var_if_defined, nan)
def variance(self, name="variance"):
"""Variance of each batch member.
Variance for inverse gamma is defined only for `alpha > 2`. If
`self.allow_nan_stats` is `False`, an exception will be raised rather
than returning `NaN`.
Args:
name: A name to give this op.
Returns:
The variance for every batch member, a `Tensor` with same `dtype` as self.
"""
alpha = self._alpha
beta = self._beta
with ops.name_scope(self.name):
with ops.op_scope([alpha, beta], name):
var_if_defined = (math_ops.square(self._beta) /
(math_ops.square(self._alpha - 1.0) *
(self._alpha - 2.0)))
if self.allow_nan_stats:
alpha_gt_2 = alpha > 2.0
nan = np.nan * self._ones()
return math_ops.select(alpha_gt_2, var_if_defined, nan)
else:
two = constant_op.constant(2.0, dtype=self.dtype)
return control_flow_ops.with_dependencies(
[check_ops.assert_less(
two, alpha,
message="variance not defined for components of alpha <= 2")],
var_if_defined)
def mean(self, name="mean"):
"""Mean of each batch member.
The mean of an inverse gamma distribution is `beta / (alpha - 1)`,
when `alpha > 1`, and `NaN` otherwise. If `self.allow_nan_stats` is
`False`, an exception will be raised rather than returning `NaN`
Args:
name: A name to give this op.
Returns:
The mean for every batch member, a `Tensor` with same `dtype` as self.
"""
alpha = self._alpha
beta = self._beta
with ops.name_scope(self.name):
with ops.op_scope([alpha, beta], name):
mean_if_defined = beta / (alpha - 1.0)
if self.allow_nan_stats:
alpha_gt_1 = alpha > 1.0
nan = np.nan * self._ones()
return math_ops.select(alpha_gt_1, mean_if_defined, nan)
else:
one = constant_op.constant(1.0, dtype=self.dtype)
return control_flow_ops.with_dependencies(
[check_ops.assert_less(
one, alpha,
message="mean not defined for components of alpha <= 1")],
mean_if_defined)
def mode(self, name="mode"):
"""Mode of each batch member.
The mode of a gamma distribution is `(alpha - 1) / beta` when `alpha > 1`,
and `NaN` otherwise. If `self.strict_statistics` is `True`, an exception
will be raised rather than returning `NaN`.
Args:
name: A name to give this op.
Returns:
The mode for every batch member, a `Tensor` with same `dtype` as self.
"""
alpha = self._alpha
beta = self._beta
with ops.name_scope(self.name):
with ops.op_scope([alpha, beta], name):
mode_if_defined = (alpha - 1.0) / beta
if self.strict_statistics:
one = ops.convert_to_tensor(1.0, dtype=self.dtype)
return control_flow_ops.with_dependencies(
[check_ops.assert_less(one, alpha)], mode_if_defined)
else:
alpha_ge_1 = alpha >= 1.0
nan = np.nan * self._ones()
return math_ops.select(alpha_ge_1, mode_if_defined, nan)
def mode(self, name="mode"):
"""Mode of each batch member.
The mode of a gamma distribution is `(alpha - 1) / beta` when `alpha > 1`,
and `NaN` otherwise. If `self.allow_nan_stats` is `False`, an exception
will be raised rather than returning `NaN`.
Args:
name: A name to give this op.
Returns:
The mode for every batch member, a `Tensor` with same `dtype` as self.
"""
alpha = self._alpha
beta = self._beta
with ops.name_scope(self.name):
with ops.name_scope(name, values=[alpha, beta]):
mode_if_defined = (alpha - 1.0) / beta
if self.allow_nan_stats:
alpha_ge_1 = alpha >= 1.0
nan = np.nan * self._ones()
return math_ops.select(alpha_ge_1, mode_if_defined, nan)
else:
one = constant_op.constant(1.0, dtype=self.dtype)
return control_flow_ops.with_dependencies(
[check_ops.assert_less(
one, alpha,
message="mode not defined for components of alpha <= 1"
)], mode_if_defined)
def test_doesnt_raise_when_both_empty(self):
with self.test_session():
larry = constant_op.constant([])
curly = constant_op.constant([])
with ops.control_dependencies([check_ops.assert_less(larry, curly)]):
out = array_ops.identity(larry)
out.eval()
def mean(self, name="mean"):
"""Mean of the distribution.
The mean of Student's T equals `mu` if `df > 1`, otherwise it is `NaN`. If
`self.allow_nan_stats=False`, then an exception will be raised rather than
returning `NaN`.
Args:
name: A name to give this op.
Returns:
The mean for every batch member, a `Tensor` with same `dtype` as self.
"""
with ops.name_scope(self.name):
with ops.name_scope(name, values=[self._mu]):
result_if_defined = self._mu * self._ones()
if self.allow_nan_stats:
df_gt_1 = self._df > self._ones()
nan = np.nan + self._zeros()
return math_ops.select(df_gt_1, result_if_defined, nan)
else:
one = constant_op.constant(1.0, dtype=self.dtype)
return control_flow_ops.with_dependencies(
[check_ops.assert_less(
one, self._df,
message="mean not defined for components of df <= 1"
)], result_if_defined)
def _variance(self):
# We need to put the tf.where inside the outer tf.where to ensure we never
# hit a NaN in the gradient.
denom = array_ops.where(math_ops.greater(self.df, 2.),
self.df - 2.,
array_ops.ones_like(self.df))
# Abs(scale) superfluous.
var = (array_ops.ones(self.batch_shape_tensor(), dtype=self.dtype) *
math_ops.square(self.scale) * self.df / denom)
# When 1 < df <= 2, variance is infinite.
inf = np.array(np.inf, dtype=self.dtype.as_numpy_dtype())
result_where_defined = array_ops.where(
self.df > array_ops.fill(self.batch_shape_tensor(), 2.),
var,
array_ops.fill(self.batch_shape_tensor(), inf, name="inf"))
if self.allow_nan_stats:
nan = np.array(np.nan, dtype=self.dtype.as_numpy_dtype())
return array_ops.where(
math_ops.greater(
self.df,
array_ops.ones(self.batch_shape_tensor(), dtype=self.dtype)),
result_where_defined,
array_ops.fill(self.batch_shape_tensor(), nan, name="nan"))
else:
return control_flow_ops.with_dependencies(
[
check_ops.assert_less(
array_ops.ones([], dtype=self.dtype),
self.df,
message="variance not defined for components of df <= 1"),
],
result_where_defined)
def test_raises_when_greater(self):
small = constant_op.constant([1, 2], name="small")
big = constant_op.constant([3, 4], name="big")
with self.assertRaisesOpError("x < y did not hold"):
with ops.control_dependencies([check_ops.assert_less(big, small)]):
out = array_ops.identity(small)
self.evaluate(out)
def mode(self, name="mode"):
"""Mode of the distribution.
Note that the mode for the Beta distribution is only defined
when `alpha > 1`. This returns the mode when `alpha > 1`,
and NaN otherwise. If `self.allow_nan_stats` is `False`, an exception
will be raised rather than returning `NaN`.
Args:
name: The name for this op.
Returns:
Mode of the Dirichlet distribution.
"""
with ops.name_scope(self.name):
with ops.op_scope([self._alpha, self._alpha_0], name):
one = constant_op.constant(1, self.dtype)
mode = (self._alpha - 1)/ (
array_ops.expand_dims(self._alpha_0, -1) - math_ops.cast(
self.event_shape()[0], self.dtype))
if self.allow_nan_stats:
return math_ops.select(
math_ops.greater(self._alpha, 1),
mode,
(constant_op.constant(float("NaN"), dtype=self.dtype) *
array_ops.ones_like(self._alpha, dtype=self.dtype)))
else:
return control_flow_ops.with_dependencies([
check_ops.assert_less(
one, self._alpha,
message="mode not defined for components of alpha <= 1")
], mode)
def __init__(self,
a=0.0,
b=1.0,
validate_args=True,
allow_nan_stats=False,
name="Uniform"):
"""Construct Uniform distributions with `a` and `b`.
The parameters `a` and `b` must be shaped in a way that supports
broadcasting (e.g. `b - a` is a valid operation).
Here are examples without broadcasting:
```python
# Without broadcasting
u1 = Uniform(3.0, 4.0) # a single uniform distribution [3, 4]
u2 = Uniform([1.0, 2.0], [3.0, 4.0]) # 2 distributions [1, 3], [2, 4]
u3 = Uniform([[1.0, 2.0],
[3.0, 4.0]],
[[1.5, 2.5],
[3.5, 4.5]]) # 4 distributions
```
And with broadcasting:
```python
u1 = Uniform(3.0, [5.0, 6.0, 7.0]) # 3 distributions
```
Args:
a: Floating point tensor, the minimum endpoint.
b: Floating point tensor, the maximum endpoint. Must be > `a`.
validate_args: Whether to assert that `a > b`. If `validate_args` is
`False` and inputs are invalid, correct behavior is not guaranteed.
allow_nan_stats: Boolean, default `False`. If `False`, raise an
exception if a statistic (e.g. mean/mode/etc...) is undefined for any
batch member. If `True`, batch members with valid parameters leading to
undefined statistics will return NaN for this statistic.
name: The name to prefix Ops created by this distribution class.
Raises:
InvalidArgumentError: if `a >= b` and `validate_args=True`.
"""
self._allow_nan_stats = allow_nan_stats
self._validate_args = validate_args
with ops.name_scope(name, values=[a, b]):
with ops.control_dependencies([check_ops.assert_less(
a, b, message="uniform not defined when a > b.")] if validate_args
else []):
a = array_ops.identity(a, name="a")
b = array_ops.identity(b, name="b")
self._a = a
self._b = b
self._name = name
self._batch_shape = common_shapes.broadcast_shape(
self._a.get_shape(), self._b.get_shape())
self._event_shape = tensor_shape.TensorShape([])
contrib_tensor_util.assert_same_float_dtype((a, b))
def test_raises_when_less_but_non_broadcastable_shapes(self):
with self.test_session():
small = constant_op.constant([1, 1, 1], name="small")
big = constant_op.constant([3, 2], name="big")
with self.assertRaisesRegexp(ValueError, "must be"):
with ops.control_dependencies([check_ops.assert_less(small, big)]):
out = array_ops.identity(small)
out.eval()
def _check_x(self, x):
"""Check x for proper shape, values, then return tensor version."""
x = ops.convert_to_tensor(x, name="x_before_deps")
dependencies = [
check_ops.assert_positive(x),
check_ops.assert_less(x, constant_op.constant(
1, self.dtype))] if self.validate_args else []
return control_flow_ops.with_dependencies(dependencies, x)
def test_raises_when_equal(self):
small = constant_op.constant([1, 2], name="small")
with self.assertRaisesOpError("failure message.*\n*.* x < y did not hold"):
with ops.control_dependencies(
[check_ops.assert_less(
small, small, message="failure message")]):
out = array_ops.identity(small)
self.evaluate(out)
def _assert_range(labels, n_classes):
assert_less = check_ops.assert_less(
labels,
ops.convert_to_tensor(n_classes, dtype=labels.dtype),
message='Label IDs must < n_classes')
assert_greater = check_ops.assert_non_negative(
labels, message='Label IDs must >= 0')
with ops.control_dependencies((assert_less, assert_greater)):
return array_ops.identity(labels)
def test_raises_when_equal(self):
with self.test_session():
small = constant_op.constant([1, 2], name="small")
with ops.control_dependencies(
[check_ops.assert_less(
small, small, message="fail")]):
out = array_ops.identity(small)
with self.assertRaisesOpError("fail.*small.*small"):
out.eval()
def _check_x(self, x):
"""Check x for proper shape, values, then return tensor version."""
x = ops.convert_to_tensor(x, name="x_before_deps")
candidate_one = math_ops.reduce_sum(x, reduction_indices=[-1])
one = constant_op.constant(1., self.dtype)
dependencies = [check_ops.assert_positive(x), check_ops.assert_less(
x, one, message="x has components greater than or equal to 1"),
distribution_util.assert_close(one, candidate_one)
] if self.validate_args else []
return control_flow_ops.with_dependencies(dependencies, x)
def _mode(self):
mode = (self.concentration1 - 1.) / (self.total_concentration - 2.)
if self.allow_nan_stats:
nan = array_ops.fill(
self.batch_shape_tensor(),
np.array(np.nan, dtype=self.dtype.as_numpy_dtype()),
name="nan")
is_defined = math_ops.logical_and(self.concentration1 > 1.,
self.concentration0 > 1.)
return array_ops.where(is_defined, mode, nan)
return control_flow_ops.with_dependencies([
check_ops.assert_less(
array_ops.ones([], dtype=self.dtype),
self.concentration1,
message="Mode undefined for concentration1 <= 1."),
check_ops.assert_less(
array_ops.ones([], dtype=self.dtype),
self.concentration0,
message="Mode undefined for concentration0 <= 1.")
], mode)
def _check_x(self, x):
"""Check x for proper shape, values, then return tensor version."""
x = ops.convert_to_tensor(x, name="x_before_deps")
candidate_one = math_ops.reduce_sum(x, reduction_indices=[-1])
one = constant_op.constant(1.0, self.dtype)
dependencies = (
[check_ops.assert_positive(x), check_ops.assert_less(x, one), _assert_close(one, candidate_one)]
if self.validate_args
else []
)
return control_flow_ops.with_dependencies(dependencies, x)
def _maybe_assert_valid_sample(self, x):
"""Checks the validity of a sample."""
if not self.validate_args:
return x
return control_flow_ops.with_dependencies([
check_ops.assert_positive(x, message="sample must be positive"),
check_ops.assert_less(
x,
array_ops.ones([], self.dtype),
message="sample must be less than `1`."),
], x)
def _assert_valid_sample(self, x):
"""Check x for proper shape, values, then return tensor version."""
if not self.validate_args: return x
return control_flow_ops.with_dependencies([
check_ops.assert_positive(
x,
message="Negative events lie outside Beta distribution support."),
check_ops.assert_less(
x, array_ops.ones((), self.dtype),
message="Event>=1 lies outside Beta distribution support."),
], x)
def __init__(
self, a=0.0, b=1.0, strict=True, strict_statistics=True, name="Uniform"):
"""Construct Uniform distributions with `a` and `b`.
The parameters `a` and `b` must be shaped in a way that supports
broadcasting (e.g. `b - a` is a valid operation).
Here are examples without broadcasting:
```python
# Without broadcasting
u1 = Uniform(3.0, 4.0) # a single uniform distribution [3, 4]
u2 = Uniform([1.0, 2.0], [3.0, 4.0]) # 2 distributions [1, 3], [2, 4]
u3 = Uniform([[1.0, 2.0],
[3.0, 4.0]],
[[1.5, 2.5],
[3.5, 4.5]]) # 4 distributions
```
And with broadcasting:
```python
u1 = Uniform(3.0, [5.0, 6.0, 7.0]) # 3 distributions
```
Args:
a: `float` or `double` tensor, the minimum endpoint.
b: `float` or `double` tensor, the maximum endpoint. Must be > `a`.
strict: Whether to assert that `a > b`. If `strict` is False and inputs
are invalid, correct behavior is not guaranteed.
strict_statistics: Boolean, default True. If True, raise an exception if
a statistic (e.g. mean/mode/etc...) is undefined for any batch member.
If False, batch members with valid parameters leading to undefined
statistics will return NaN for this statistic.
name: The name to prefix Ops created by this distribution class.
Raises:
InvalidArgumentError: if `a >= b` and `strict=True`.
"""
self._strict_statistics = strict_statistics
self._strict = strict
with ops.op_scope([a, b], name):
with ops.control_dependencies(
[check_ops.assert_less(a, b)] if strict else []):
a = array_ops.identity(a, name="a")
b = array_ops.identity(b, name="b")
self._a = a
self._b = b
self._name = name
self._batch_shape = self._ones().get_shape()
self._event_shape = tensor_shape.TensorShape([])
contrib_tensor_util.assert_same_float_dtype((a, b))
def _mode(self):
a = self.concentration1
b = self.concentration0
mode = ((a - 1) / (a * b - 1))**(1. / a)
if self.allow_nan_stats:
nan = array_ops.fill(
self.batch_shape_tensor(),
np.array(np.nan, dtype=self.dtype.as_numpy_dtype),
name="nan")
is_defined = (self.concentration1 > 1.) & (self.concentration0 > 1.)
return array_ops.where(is_defined, mode, nan)
return control_flow_ops.with_dependencies([
check_ops.assert_less(
array_ops.ones([], dtype=self.dtype),
self.concentration1,
message="Mode undefined for concentration1 <= 1."),
check_ops.assert_less(
array_ops.ones([], dtype=self.dtype),
self.concentration0,
message="Mode undefined for concentration0 <= 1.")
], mode)
def _FakeQuantWithMinMaxVars(inputs, min_var, max_var, per_channel, num_bits,
narrow_range):
"""Adds a fake quantization operation.
Depending on value of per_channel, this operation may do global quantization
or per channel quantization. min_var and max_var should have corresponding
shapes: [1] when per_channel == False and [d] when per_channel == True.
Args:
inputs: a tensor containing values to be quantized.
min_var: a variable containing quantization range lower end(s).
max_var: a variable containing quantization range lupper end(s).
per_channel: a boolean specifying whether to use per-channel quantizatioh.
num_bits: Number of bits to use for quantization, must be between 2 and 8.
narrow_range: Whether to use the narrow quantization range
[1; 2^num_bits - 1] or wide range [0; 2^num_bits - 1].
Returns:
a tensor containing quantized values.
"""
if per_channel:
assert len(min_var.get_shape()) == 1
assert len(max_var.get_shape()) == 1
with ops.control_dependencies([check_ops.assert_less(min_var, max_var)]):
return array_ops.fake_quant_with_min_max_vars_per_channel(
inputs,
min_var,
max_var,
num_bits=num_bits,
narrow_range=narrow_range)
else:
assert min_var.get_shape() == [] # pylint: disable=g-explicit-bool-comparison
assert max_var.get_shape() == [] # pylint: disable=g-explicit-bool-comparison
with ops.control_dependencies([check_ops.assert_less(min_var, max_var)]):
return array_ops.fake_quant_with_min_max_vars(
inputs,
min_var,
max_var,
num_bits=num_bits,
narrow_range=narrow_range)
def _maybe_assert_valid_concentration(self, concentration, validate_args):
"""Checks the validity of the concentration parameter."""
if not validate_args:
return concentration
return control_flow_ops.with_dependencies([
check_ops.assert_positive(
concentration,
message="Concentration parameter must be positive."),
check_ops.assert_rank_at_least(
concentration,
1,
message="Concentration parameter must have >=1 dimensions."),
check_ops.assert_less(
1,
array_ops.shape(concentration)[-1],
message="Concentration parameter must have event_size >= 2."),
], concentration)
def _variance(self):
var = (math_ops.square(self.rate) /
math_ops.square(self.concentration - 1.) /
(self.concentration - 2.))
if self.allow_nan_stats:
nan = array_ops.fill(self.batch_shape_tensor(),
np.array(np.nan,
dtype=self.dtype.as_numpy_dtype()),
name="nan")
return array_ops.where(self.concentration > 2., var, nan)
else:
return control_flow_ops.with_dependencies([
check_ops.assert_less(
constant_op.constant(2., dtype=self.dtype),
self.concentration,
message="variance undefined when any concentration <= 2"),
], var)
def _mode(self):
k = math_ops.cast(self.event_shape_tensor()[0], self.dtype)
mode = (self.concentration - 1.) / (
self.total_concentration[..., array_ops.newaxis] - k)
if self.allow_nan_stats:
nan = array_ops.fill(
array_ops.shape(mode),
np.array(np.nan, dtype=self.dtype.as_numpy_dtype()),
name="nan")
return array_ops.where_v2(
math_ops.reduce_all(self.concentration > 1., axis=-1), mode, nan)
return control_flow_ops.with_dependencies([
check_ops.assert_less(
array_ops.ones([], self.dtype),
self.concentration,
message="Mode undefined when any concentration <= 1"),
], mode)
def _mode(self):
mode = ((self.alpha - 1.) /
(array_ops.expand_dims(self.alpha_sum, dim=-1) -
math_ops.cast(self.event_shape()[0], self.dtype)))
if self.allow_nan_stats:
nan = np.array(np.nan, dtype=self.dtype.as_numpy_dtype())
shape = array_ops.concat(0, (self.batch_shape(), self.event_shape()))
return array_ops.where(
math_ops.greater(self.alpha, 1.),
mode,
array_ops.fill(shape, nan, name="nan"))
else:
return control_flow_ops.with_dependencies([
check_ops.assert_less(
array_ops.ones((), dtype=self.dtype), self.alpha,
message="mode not defined for components of alpha <= 1")
], mode)
def _assert_non_singular(self):
"""Private default implementation of _assert_non_singular."""
logging.warn(
"Using (possibly slow) default implementation of assert_non_singular."
" Requires conversion to a dense matrix and O(N^3) operations.")
if self._can_use_cholesky():
return self.assert_positive_definite()
else:
singular_values = linalg_ops.svd(
self._get_cached_dense_matrix(), compute_uv=False)
# TODO(langmore) Add .eig and .cond as methods.
cond = (math_ops.reduce_max(singular_values, axis=-1) /
math_ops.reduce_min(singular_values, axis=-1))
return check_ops.assert_less(
cond,
self._max_condition_number_to_be_non_singular(),
message="Singular matrix up to precision epsilon.")
def _assert_close(expected, actual, rtol=1e-04, name='assert_close'):
with ops.name_scope(name, 'assert_close', (expected, actual, rtol)) as scope:
expected = ops.convert_to_tensor(expected, name='expected')
actual = ops.convert_to_tensor(actual, name='actual')
rdiff = math_ops.abs(expected - actual, 'diff') / math_ops.abs(expected)
rtol = ops.convert_to_tensor(rtol, name='rtol')
return check_ops.assert_less(
rdiff,
rtol,
data=(
'Condition expected =~ actual did not hold element-wise:'
'expected = ', expected,
'actual = ', actual,
'rdiff = ', rdiff,
'rtol = ', rtol,
),
name=scope)
def __init__(self,
low=0.,
high=1.,
validate_args=False,
allow_nan_stats=True,
name="Uniform"):
"""Initialize a batch of Uniform distributions.
Args:
low: Floating point tensor, lower boundary of the output interval. Must
have `low < high`.
high: Floating point tensor, upper boundary of the output interval. Must
have `low < high`.
validate_args: Python `bool`, default `False`. When `True` distribution
parameters are checked for validity despite possibly degrading runtime
performance. When `False` invalid inputs may silently render incorrect
outputs.
allow_nan_stats: Python `bool`, default `True`. When `True`, statistics
(e.g., mean, mode, variance) use the value "`NaN`" to indicate the
result is undefined. When `False`, an exception is raised if one or
more of the statistic's batch members are undefined.
name: Python `str` name prefixed to Ops created by this class.
Raises:
InvalidArgumentError: if `low >= high` and `validate_args=False`.
"""
parameters = dict(locals())
with ops.name_scope(name, values=[low, high]) as name:
with ops.control_dependencies([
check_ops.assert_less(
low,
high,
message="uniform not defined when low >= high.")
] if validate_args else []):
self._low = array_ops.identity(low, name="low")
self._high = array_ops.identity(high, name="high")
check_ops.assert_same_float_dtype([self._low, self._high])
super(Uniform, self).__init__(
dtype=self._low.dtype,
reparameterization_type=distribution.FULLY_REPARAMETERIZED,
validate_args=validate_args,
allow_nan_stats=allow_nan_stats,
parameters=parameters,
graph_parents=[self._low, self._high],
name=name)
def assert_no_entries_with_modulus_zero(
x, message=None, name="assert_no_entries_with_modulus_zero"):
"""Returns `Op` that asserts Tensor `x` has no entries with modulus zero.
Args:
x: Numeric `Tensor`, real, integer, or complex.
message: A string message to prepend to failure message.
name: A name to give this `Op`.
Returns:
An `Op` that asserts `x` has no entries with modulus zero.
"""
with ops.name_scope(name, values=[x]):
x = ops.convert_to_tensor(x, name="x")
dtype = x.dtype.base_dtype
should_be_nonzero = math_ops.abs(x)
zero = ops.convert_to_tensor(0, dtype=dtype.real_dtype)
return check_ops.assert_less(zero, should_be_nonzero, message=message)
def _mean(self):
mean = self.loc * array_ops.ones(self.batch_shape_tensor(),
dtype=self.dtype)
if self.allow_nan_stats:
nan = np.array(np.nan, dtype=self.dtype.as_numpy_dtype())
return array_ops.where(
math_ops.greater(
self.df,
array_ops.ones(self.batch_shape_tensor(),
dtype=self.dtype)), mean,
array_ops.fill(self.batch_shape_tensor(), nan, name="nan"))
else:
return control_flow_ops.with_dependencies([
check_ops.assert_less(
array_ops.ones([], dtype=self.dtype),
self.df,
message="mean not defined for components of df <= 1"),
], mean)
def _verify_input(data, labels, probs):
"""Verify that batched inputs are well-formed."""
# Probabilities must be able to be converted to a 1D non-object numpy array.
probs = np.asarray(probs)
if probs.dtype == np.dtype('object'):
raise ValueError(
'Probabilities must be able to be converted to a numpy '
'array.')
if len(probs.shape) != 1:
raise ValueError('Probabilities must be 1D.')
# Probabilities must sum to one.
# TODO(joelshor): Investigate whether logits should be passed instead of
# probs.
if not np.isclose(np.sum(probs), 1.0):
raise ValueError('Probabilities must sum to one.', np.sum(probs))
# Labels tensor should only have batch dimension.
labels.get_shape().assert_has_rank(1)
# Data tensor should have a batch dimension.
data_shape = data.get_shape().with_rank_at_least(1)
# Data and label batch dimensions must be compatible.
data_shape[0].assert_is_compatible_with(labels.get_shape()[0])
# Data and labels must have the same, strictly positive batch size. Since we
# can't assume we know the batch size at graph creation, add runtime checks.
data_batch_size = array_ops.shape(data)[0]
labels_batch_size = array_ops.shape(labels)[0]
data = control_flow_ops.with_dependencies([
check_ops.assert_positive(data_batch_size),
check_ops.assert_equal(data_batch_size, labels_batch_size)
], data)
# Label's classes must be integers 0 <= x < num_classes.
labels = control_flow_ops.with_dependencies([
check_ops.assert_integer(labels),
check_ops.assert_non_negative(labels),
check_ops.assert_less(labels, math_ops.cast(len(probs), labels.dtype))
], labels)
return data, labels, probs
def variance(self, name="variance"):
"""Variance of the distribution.
Variance for Student's T equals
```
df / (df - 2), when df > 2
infinity, when 1 < df <= 2
NaN, when df <= 1
```
The NaN state occurs because mean is undefined for `df <= 1`, and if
`self.allow_nan_stats` is `False`, an exception will be raised if any batch
members fall into this state.
Args:
name: A name for this op.
Returns:
The variance for every batch member, a `Tensor` with same `dtype` as self.
"""
with ops.name_scope(self.name):
with ops.name_scope(name, values=[self._df, self._sigma]):
result_where_finite = (
self._zeros() + math_ops.square(self._sigma) * self._df /
(self._df - 2))
# When 1 < df <= 2, variance is infinite.
result_where_defined = math_ops.select(
self._zeros() + self._df > 2, result_where_finite,
self._zeros() + np.inf)
if self.allow_nan_stats:
return math_ops.select((self._zeros() + self._df > 1),
result_where_defined,
self._zeros() + np.nan)
else:
one = constant_op.constant(1.0, dtype=self.dtype)
return control_flow_ops.with_dependencies([
check_ops.assert_less(
one,
self._df,
message=
"variance not defined for components of df <= 1")
], result_where_defined)
def __init__(self, a=0.0, b=1.0, name="Uniform"):
"""Construct Uniform distributions with `a` and `b`.
The parameters `a` and `b` must be shaped in a way that supports
broadcasting (e.g. `b - a` is a valid operation).
Here are examples without broadcasting:
```python
# Without broadcasting
u1 = Uniform(3.0, 4.0) # a single uniform distribution [3, 4]
u2 = Uniform([1.0, 2.0], [3.0, 4.0]) # 2 distributions [1, 3], [2, 4]
u3 = Uniform([[1.0, 2.0],
[3.0, 4.0]],
[[1.5, 2.5],
[3.5, 4.5]]) # 4 distributions
```
And with broadcasting:
```python
u1 = Uniform(3.0, [5.0, 6.0, 7.0]) # 3 distributions
```
Args:
a: `float` or `double` tensor, the minimum endpoint.
b: `float` or `double` tensor, the maximum endpoint. Must be > `a`.
name: The name to prefix Ops created by this distribution class.
Raises:
InvalidArgumentError: if `a >= b`.
"""
with ops.op_scope([a, b], name):
with ops.control_dependencies([check_ops.assert_less(a, b)]):
a = array_ops.identity(a, name="a")
b = array_ops.identity(b, name="b")
self._a = a
self._b = b
self._name = name
self._batch_shape = self._ones().get_shape()
self._event_shape = tensor_shape.TensorShape([])
contrib_tensor_util.assert_same_float_dtype((a, b))
def assert_hermitian_spectrum(self, name="assert_hermitian_spectrum"):
"""Returns an `Op` that asserts this operator has Hermitian spectrum.
This operator corresponds to a real-valued matrix if and only if its
spectrum is Hermitian.
Args:
name: A name to give this `Op`.
Returns:
An `Op` that asserts this operator has Hermitian spectrum.
"""
eps = np.finfo(self.dtype.real_dtype.as_numpy_dtype).eps
with self._name_scope(name): # pylint: disable=not-callable
# Assume linear accumulation of error.
max_err = eps * self.domain_dimension_tensor()
imag_convolution_kernel = math_ops.imag(self.convolution_kernel())
return check_ops.assert_less(math_ops.abs(imag_convolution_kernel),
max_err,
message="Spectrum was not Hermitian")
def _assert_close(
expected, actual, rtol=1e-04, message='', name='assert_close'):
with ops.name_scope(name, 'assert_close', (expected, actual, rtol)) as scope:
expected = ops.convert_to_tensor(expected, name='expected')
actual = ops.convert_to_tensor(actual, name='actual')
rdiff = math_ops.abs((expected - actual) / expected, 'diff')
rtol = ops.convert_to_tensor(rtol, name='rtol')
return check_ops.assert_less(
rdiff,
rtol,
data=(
message,
'Condition expected =~ actual did not hold element-wise:'
'expected = ', expected,
'actual = ', actual,
'rdiff = ', rdiff,
'rtol = ', rtol,
),
summarize=expected.get_shape().num_elements(),
name=scope)
def batching_fn(bucket_id, grouped_dataset):
"""Batch elements in dataset."""
batch_size = batch_sizes[bucket_id]
none_filler = None
if pad_to_bucket_boundary:
err_msg = ("When pad_to_bucket_boundary=True, elements must have "
"length <= max(bucket_boundaries).")
check = check_ops.assert_less(
bucket_id,
constant_op.constant(len(bucket_batch_sizes) - 1,
dtype=dtypes.int64),
message=err_msg)
with ops.control_dependencies([check]):
boundaries = constant_op.constant(bucket_boundaries,
dtype=dtypes.int64)
bucket_boundary = boundaries[bucket_id]
none_filler = bucket_boundary
shapes = make_padded_shapes(
padded_shapes or grouped_dataset.output_shapes,
none_filler=none_filler)
return grouped_dataset.padded_batch(batch_size, shapes, padding_values)
def _variance(self):
var = (self._ones() * math_ops.square(self.sigma) * self.df /
(self.df - 2))
# When 1 < df <= 2, variance is infinite.
inf = np.array(np.inf, dtype=self.dtype.as_numpy_dtype())
result_where_defined = array_ops.where(
math_ops.greater(self.df, array_ops.fill(self.batch_shape(), 2.)),
var, array_ops.fill(self.batch_shape(), inf, name="inf"))
if self.allow_nan_stats:
nan = np.array(np.nan, dtype=self.dtype.as_numpy_dtype())
return array_ops.where(
math_ops.greater(self.df, self._ones()), result_where_defined,
array_ops.fill(self.batch_shape(), nan, name="nan"))
else:
return control_flow_ops.with_dependencies([
check_ops.assert_less(
array_ops.ones((), dtype=self.dtype),
self.df,
message="variance not defined for components of df <= 1"),
], result_where_defined)
def _process_labels(self, labels):
if labels is None:
raise ValueError(
'You must provide a labels Tensor. Given: None. '
'Suggested troubleshooting steps: Check that your data contain '
'your label feature. Check that your input_fn properly parses and '
'returns labels.')
if isinstance(labels, sparse_tensor.SparseTensor):
if labels.dtype == dtypes.string:
label_ids_values = lookup_ops.index_table_from_tensor(
vocabulary_list=tuple(self._label_vocabulary),
name='class_id_lookup').lookup(labels.values)
label_ids = sparse_tensor.SparseTensor(
indices=labels.indices,
values=label_ids_values,
dense_shape=labels.dense_shape)
return math_ops.to_int64(
sparse_ops.sparse_to_indicator(label_ids, self._n_classes))
else:
err_msg = (
r'labels must be an integer SparseTensor with values in '
r'[0, {})'.format(self._n_classes))
assert_int = check_ops.assert_integer(labels.values,
message=err_msg)
assert_less = check_ops.assert_less(labels.values,
ops.convert_to_tensor(
self._n_classes,
dtype=labels.dtype),
message=err_msg)
assert_greater = check_ops.assert_non_negative(labels.values,
message=err_msg)
with ops.control_dependencies(
[assert_int, assert_less, assert_greater]):
return math_ops.to_int64(
sparse_ops.sparse_to_indicator(labels,
self._n_classes))
err_msg = (
r'labels must be an integer indicator Tensor with values in [0, 1]'
)
return head_lib._assert_range(labels, 2, message=err_msg) # pylint:disable=protected-access,
def _label_ids(self, labels):
"""Converts labels to integer id space."""
if self._label_vocabulary is None:
if not labels.dtype.is_integer:
raise ValueError('Labels dtype should be integer '
'Instead got %s.' % labels.dtype)
label_ids = labels
else:
if labels.dtype != dtypes.string:
raise ValueError('Labels dtype should be string if there is a '
'vocabulary. Instead got {}'.format(labels.dtype))
label_ids = lookup_ops.index_table_from_tensor(
vocabulary_list=tuple(self._label_vocabulary),
name='class_id_lookup').lookup(labels)
assert_less = check_ops.assert_less(
label_ids,
ops.convert_to_tensor(self._n_classes, dtype=label_ids.dtype),
message='Label IDs must < n_classes')
assert_greater = check_ops.assert_non_negative(
label_ids, message='Label Ids must >= 0')
with ops.control_dependencies((assert_less, assert_greater)):
return array_ops.identity(label_ids)
def __init__(self,
low=0.,
high=1.,
temp=1e2,
validate_args=False,
allow_nan_stats=True,
squared=True,
activation=tf.nn.relu,
name="SoftUniform"):
parameters = locals()
parameters = dict(locals())
self._activation = activation
self._squared = squared
with ops.name_scope(name, values=[low, high]) as name:
with ops.control_dependencies([
check_ops.assert_less(
low,
high,
message="uniform not defined when low >= high.")
] if validate_args else []):
self._low = array_ops.identity(low, name="low")
self._high = array_ops.identity(high, name="high")
self._temp = array_ops.identity(temp, name="temp")
check_ops.assert_same_float_dtype(
[self._low, self._high, self._temp])
super(SoftUniform,
self).__init__(dtype=self._low.dtype,
reparameterization_type=ds.FULLY_REPARAMETERIZED,
validate_args=validate_args,
allow_nan_stats=allow_nan_stats,
parameters=parameters,
graph_parents=[self._low, self._high, self._temp],
name=name)
def _variance(self):
variance = (math_ops.square(self.scale) * (self.concentration - 1) /
(math_ops.square(self.concentration - 1) *
(self.concentration - 2)))
if self.allow_nan_stats:
nan = array_ops.fill(self.batch_shape_tensor(),
np.array(np.nan,
dtype=self.dtype.as_numpy_dtype()),
name="nan")
inf = array_ops.fill(self.batch_shape_tensor(),
np.array(np.inf,
dtype=self.dtype.as_numpy_dtype()),
name="inf")
return array_ops.where(
self.concentration > 2., variance,
array_ops.where(self.concentration > 1., inf, nan))
else:
return control_flow_ops.with_dependencies([
check_ops.assert_less(
array_ops.ones([], self.dtype),
self.concentration,
message="variance not defined when any concentration <= 1"
),
], variance)
def mean(self, name="mean"):
"""Mean of the distribution.
The mean of Student's T equals `mu` if `df > 1`, otherwise it is `NaN`. If
`self.strict_statistics=True`, then an exception will be raised rather than
returning `NaN`.
Args:
name: A name to give this op.
Returns:
The mean for every batch member, a `Tensor` with same `dtype` as self.
"""
with ops.name_scope(self.name):
with ops.op_scope([self._mu], name):
result_if_defined = self._mu * self._ones()
if self.strict_statistics:
one = ops.convert_to_tensor(1.0, dtype=self.dtype)
return control_flow_ops.with_dependencies(
[check_ops.assert_less(one, self._df)], result_if_defined)
else:
df_gt_1 = self._df > self._ones()
nan = np.nan + self._zeros()
return math_ops.select(df_gt_1, result_if_defined, nan)
def stack_dynamic_partitions(data, partitions, num_partitions, name=None):
"""Stacks dynamic partitions of a Tensor or RaggedTensor.
Returns a RaggedTensor `output` with `num_partitions` rows, where the row
`output[i]` is formed by stacking all slices `data[j1...jN]` such that
`partitions[j1...jN] = i`. Slices of `data` are stacked in row-major
order.
If `num_partitions` is an `int` (not a `Tensor`), then this is equivalent to
`tf.ragged.stack(tf.dynamic_partition(data, partitions, num_partitions))`.
#### Example:
>>> data = ['a', 'b', 'c', 'd', 'e']
>>> partitions = [ 3, 0, 2, 2, 3]
>>> num_partitions = 5
>>> tf.ragged.stack_dynamic_partitions(data, partitions, num_partitions)
<tf.RaggedTensor [[b'b'], [], [b'c', b'd'], [b'a', b'e'], []]>
Args:
data: A `Tensor` or `RaggedTensor` containing the values to stack.
partitions: An `int32` or `int64` `Tensor` or `RaggedTensor` specifying the
partition that each slice of `data` should be added to. `partitions.shape`
must be a prefix of `data.shape`. Values must be greater than or equal to
zero, and less than `num_partitions`. `partitions` is not required to be
sorted.
num_partitions: An `int32` or `int64` scalar specifying the number of
partitions to output. This determines the number of rows in `output`.
name: A name prefix for the returned tensor (optional).
Returns:
A `RaggedTensor` containing the stacked partitions. The returned tensor
has the same dtype as `data`, and its shape is
`[num_partitions, (D)] + data.shape[partitions.rank:]`, where `(D)` is a
ragged dimension whose length is the number of data slices stacked for
each `partition`.
"""
with ops.name_scope(name, 'SegmentStack', [data, partitions, num_partitions]):
# Convert inputs to tensors.
data = ragged_tensor.convert_to_tensor_or_ragged_tensor(data, name='data')
row_splits_dtype = (
data.row_splits.dtype
if isinstance(data, ragged_tensor.RaggedTensor) else None)
partitions = ragged_tensor.convert_to_tensor_or_ragged_tensor(
partitions, name='partitions', preferred_dtype=row_splits_dtype)
num_partitions = ops.convert_to_tensor(
num_partitions, name='num_partitions', preferred_dtype=partitions.dtype)
if row_splits_dtype is not None:
partitions = math_ops.cast(partitions, row_splits_dtype)
num_partitions = math_ops.cast(num_partitions, partitions.dtype)
# Sanity-checks for shapes.
partitions_rank = partitions.shape.ndims
if partitions_rank is None:
raise ValueError('partitions must have known rank.')
num_partitions.shape.assert_has_rank(0)
partitions.shape.assert_is_compatible_with(data.shape[:partitions_rank])
if partitions_rank == 0:
# If partitions is a scalar, then just create a RaggedTensor containing
# that single the complete `data` value in the specified row.
return ragged_tensor.RaggedTensor.from_value_rowids(
values=array_ops.stack([data]),
value_rowids=array_ops.stack([partitions]),
nrows=num_partitions,
validate=False)
elif partitions_rank == 1:
# If partitions is a vector (the typical case): we can just use data and
# partitions as the `values` and `value_rowids` for `from_value_rowids`,
# as long as we sort them first.
permutation = sort_ops.argsort(partitions, stable=True)
value_rowids = array_ops.gather(partitions, permutation)
values = array_ops.gather(data, permutation)
check = check_ops.assert_less(
value_rowids[-1:],
num_partitions,
message='partitions must be less than num_partitions')
with ops.control_dependencies([check]):
return ragged_tensor.RaggedTensor.from_value_rowids(
values, value_rowids, nrows=num_partitions, validate=False)
else:
# Handle higher-dimensional partitions via recursion.
if not isinstance(data, ragged_tensor.RaggedTensor):
data = ragged_tensor.RaggedTensor.from_tensor(
data, row_splits_dtype=partitions.dtype, ragged_rank=1)
if not isinstance(partitions, ragged_tensor.RaggedTensor):
partitions = ragged_tensor.RaggedTensor.from_tensor(
partitions,
row_splits_dtype=partitions.dtype,
ragged_rank=max(data.ragged_rank, partitions_rank - 1))
check = check_ops.assert_equal(
data.row_splits,
partitions.row_splits,
message='data and partitions have incompatible ragged shapes')
with ops.control_dependencies([check]):
return stack_dynamic_partitions(data.values, partitions.values,
num_partitions)
def _verify_input(tensor_list, labels, probs_list):
"""Verify that batched inputs are well-formed."""
checked_probs_list = []
for probs in probs_list:
# Since number of classes shouldn't change at runtime, probabilities shape
# should be fully defined.
probs.get_shape().assert_is_fully_defined()
# Probabilities must be 1D.
probs.get_shape().assert_has_rank(1)
# Probabilities must be nonnegative and sum to one.
tol = 1e-6
prob_sum = math_ops.reduce_sum(probs)
checked_probs = control_flow_ops.with_dependencies([
check_ops.assert_non_negative(probs),
check_ops.assert_less(prob_sum, 1.0 + tol),
check_ops.assert_less(1.0 - tol, prob_sum)
], probs)
checked_probs_list.append(checked_probs)
# All probabilities should be the same length.
prob_length = checked_probs_list[0].get_shape().num_elements()
for checked_prob in checked_probs_list:
if checked_prob.get_shape().num_elements() != prob_length:
raise ValueError(
'Probability parameters must have the same length.')
# Labels tensor should only have batch dimension.
labels.get_shape().assert_has_rank(1)
for tensor in tensor_list:
# Data tensor should have a batch dimension.
shape = tensor.get_shape().with_rank_at_least(1)
# Data and label batch dimensions must be compatible.
tensor_shape.dimension_at_index(shape, 0).assert_is_compatible_with(
labels.get_shape()[0])
# Data and labels must have the same, strictly positive batch size. Since we
# can't assume we know the batch size at graph creation, add runtime checks.
labels_batch_size = array_ops.shape(labels)[0]
lbl_assert = check_ops.assert_positive(labels_batch_size)
# Make each tensor depend on its own checks.
labels = control_flow_ops.with_dependencies([lbl_assert], labels)
tensor_list = [
control_flow_ops.with_dependencies([
lbl_assert,
check_ops.assert_equal(array_ops.shape(x)[0], labels_batch_size)
], x) for x in tensor_list
]
# Label's classes must be integers 0 <= x < num_classes.
labels = control_flow_ops.with_dependencies([
check_ops.assert_integer(labels),
check_ops.assert_non_negative(labels),
check_ops.assert_less(labels, math_ops.cast(prob_length, labels.dtype))
], labels)
return tensor_list, labels, checked_probs_list
def __init__(self,
distribution,
low=None,
high=None,
validate_args=False,
name="QuantizedDistribution"):
"""Construct a Quantized Distribution representing `Y = ceiling(X)`.
Some properties are inherited from the distribution defining `X`. Example:
`allow_nan_stats` is determined for this `QuantizedDistribution` by reading
the `distribution`.
Args:
distribution: The base distribution class to transform. Typically an
instance of `Distribution`.
low: `Tensor` with same `dtype` as this distribution and shape
able to be added to samples. Should be a whole number. Default `None`.
If provided, base distribution's `prob` should be defined at
`low`.
high: `Tensor` with same `dtype` as this distribution and shape
able to be added to samples. Should be a whole number. Default `None`.
If provided, base distribution's `prob` should be defined at
`high - 1`.
`high` must be strictly greater than `low`.
validate_args: Python `bool`, default `False`. When `True` distribution
parameters are checked for validity despite possibly degrading runtime
performance. When `False` invalid inputs may silently render incorrect
outputs.
name: Python `str` name prefixed to Ops created by this class.
Raises:
TypeError: If `dist_cls` is not a subclass of
`Distribution` or continuous.
NotImplementedError: If the base distribution does not implement `cdf`.
"""
parameters = locals()
values = (list(distribution.parameters.values()) + [low, high])
with ops.name_scope(name, values=values) as ns:
self._dist = distribution
if low is not None:
low = ops.convert_to_tensor(low, name="low")
if high is not None:
high = ops.convert_to_tensor(high, name="high")
contrib_tensor_util.assert_same_float_dtype(
tensors=[self.distribution, low, high])
# We let QuantizedDistribution access _graph_parents since this class is
# more like a baseclass.
graph_parents = self._dist._graph_parents # pylint: disable=protected-access
checks = []
if low is not None and high is not None:
message = "low must be strictly less than high."
checks.append(check_ops.assert_less(low, high,
message=message))
self._validate_args = validate_args # self._check_integer uses this.
with ops.control_dependencies(checks if validate_args else []):
if low is not None:
self._low = self._check_integer(low)
graph_parents += [self._low]
else:
self._low = None
if high is not None:
self._high = self._check_integer(high)
graph_parents += [self._high]
else:
self._high = None
super(QuantizedDistribution, self).__init__(
dtype=self._dist.dtype,
reparameterization_type=distributions.NOT_REPARAMETERIZED,
validate_args=validate_args,
allow_nan_stats=self._dist.allow_nan_stats,
parameters=parameters,
graph_parents=graph_parents,
name=ns)
def __init__(self,
distribution,
lower_cutoff=None,
upper_cutoff=None,
name="QuantizedDistribution"):
"""Construct a Quantized Distribution representing `Y = ceiling(X)`.
Some properties are inherited from the distribution defining `X`.
In particular, `validate_args` and `allow_nan_stats` are determined for this
`QuantizedDistribution` by reading the `distribution`.
Args:
distribution: The base distribution class to transform. Typically an
instance of `Distribution`.
lower_cutoff: `Tensor` with same `dtype` as this distribution and shape
able to be added to samples. Should be a whole number. Default `None`.
If provided, base distribution's pdf/pmf should be defined at
`lower_cutoff`.
upper_cutoff: `Tensor` with same `dtype` as this distribution and shape
able to be added to samples. Should be a whole number. Default `None`.
If provided, base distribution's pdf/pmf should be defined at
`upper_cutoff - 1`.
`upper_cutoff` must be strictly greater than `lower_cutoff`.
name: The name for the distribution.
Raises:
TypeError: If `dist_cls` is not a subclass of
`Distribution` or continuous.
NotImplementedError: If the base distribution does not implement `cdf`.
"""
values = (list(distribution.parameters.values()) +
[lower_cutoff, upper_cutoff])
with ops.name_scope(name, values=values):
self._dist = distribution
super(QuantizedDistribution,
self).__init__(dtype=self._dist.dtype,
parameters={
"distribution": distribution,
"lower_cutoff": lower_cutoff,
"upper_cutoff": upper_cutoff,
},
is_continuous=False,
is_reparameterized=False,
validate_args=self._dist.validate_args,
allow_nan_stats=self._dist.allow_nan_stats,
name=name)
if lower_cutoff is not None:
lower_cutoff = ops.convert_to_tensor(lower_cutoff,
name="lower_cutoff")
if upper_cutoff is not None:
upper_cutoff = ops.convert_to_tensor(upper_cutoff,
name="upper_cutoff")
contrib_tensor_util.assert_same_float_dtype(
tensors=[self.distribution, lower_cutoff, upper_cutoff])
checks = []
if lower_cutoff is not None and upper_cutoff is not None:
message = "lower_cutoff must be strictly less than upper_cutoff."
checks.append(
check_ops.assert_less(lower_cutoff,
upper_cutoff,
message=message))
with ops.control_dependencies(
checks if self.validate_args else []):
if lower_cutoff is not None:
self._lower_cutoff = self._check_integer(lower_cutoff)
else:
self._lower_cutoff = None
if upper_cutoff is not None:
self._upper_cutoff = self._check_integer(upper_cutoff)
else:
self._upper_cutoff = None
def __init__(self,
distribution,
lower_cutoff=None,
upper_cutoff=None,
validate_args=False,
name="QuantizedDistribution"):
"""Construct a Quantized Distribution representing `Y = ceiling(X)`.
Some properties are inherited from the distribution defining `X`. Example:
`allow_nan_stats` is determined for this `QuantizedDistribution` by reading
the `distribution`.
Args:
distribution: The base distribution class to transform. Typically an
instance of `Distribution`.
lower_cutoff: `Tensor` with same `dtype` as this distribution and shape
able to be added to samples. Should be a whole number. Default `None`.
If provided, base distribution's `prob` should be defined at
`lower_cutoff`.
upper_cutoff: `Tensor` with same `dtype` as this distribution and shape
able to be added to samples. Should be a whole number. Default `None`.
If provided, base distribution's `prob` should be defined at
`upper_cutoff - 1`.
`upper_cutoff` must be strictly greater than `lower_cutoff`.
validate_args: Python boolean. Whether to validate input with asserts.
If `validate_args` is `False`, and the inputs are invalid,
correct behavior is not guaranteed.
name: The name for the distribution.
Raises:
TypeError: If `dist_cls` is not a subclass of
`Distribution` or continuous.
NotImplementedError: If the base distribution does not implement `cdf`.
"""
parameters = locals()
parameters.pop("self")
values = (list(distribution.parameters.values()) +
[lower_cutoff, upper_cutoff])
with ops.name_scope(name, values=values) as ns:
self._dist = distribution
if lower_cutoff is not None:
lower_cutoff = ops.convert_to_tensor(lower_cutoff,
name="lower_cutoff")
if upper_cutoff is not None:
upper_cutoff = ops.convert_to_tensor(upper_cutoff,
name="upper_cutoff")
contrib_tensor_util.assert_same_float_dtype(
tensors=[self.distribution, lower_cutoff, upper_cutoff])
# We let QuantizedDistribution access _graph_parents since this class is
# more like a baseclass.
graph_parents = self._dist._graph_parents # pylint: disable=protected-access
checks = []
if lower_cutoff is not None and upper_cutoff is not None:
message = "lower_cutoff must be strictly less than upper_cutoff."
checks.append(
check_ops.assert_less(lower_cutoff,
upper_cutoff,
message=message))
self._validate_args = validate_args # self._check_integer uses this.
with ops.control_dependencies(checks if validate_args else []):
if lower_cutoff is not None:
self._lower_cutoff = self._check_integer(lower_cutoff)
graph_parents += [self._lower_cutoff]
else:
self._lower_cutoff = None
if upper_cutoff is not None:
self._upper_cutoff = self._check_integer(upper_cutoff)
graph_parents += [self._upper_cutoff]
else:
self._upper_cutoff = None
super(QuantizedDistribution, self).__init__(
dtype=self._dist.dtype,
is_continuous=False,
reparameterization_type=distributions.NOT_REPARAMETERIZED,
validate_args=validate_args,
allow_nan_stats=self._dist.allow_nan_stats,
parameters=parameters,
graph_parents=graph_parents,
name=ns)
def from_value_rowids(cls,
value_rowids,
nrows=None,
validate=True,
preferred_dtype=None):
"""Creates a `RowPartition` with rows partitioned by `value_rowids`.
This `RowPartition` divides a sequence `values` into rows by specifying
which row each value should be added to:
```python
rows = [[] for _ in nrows]
for (value, rowid) in zip(values, value_rowids):
rows[rowid].append(value)
``
Args:
value_rowids: A 1-D integer tensor with shape `[nvals]`, which corresponds
one-to-one with `values`, and specifies each value's row index. Must be
nonnegative, and must be sorted in ascending order.
nrows: An integer scalar specifying the number of rows. This should be
specified if the `RowPartition` may containing empty training rows. Must
be greater than `value_rowids[-1]` (or greater than or equal to zero if
`value_rowids` is empty). Defaults to `value_rowids[-1]` (or zero if
`value_rowids` is empty).
validate: If true, then use assertions to check that the arguments form a
valid `RowPartition`.
preferred_dtype: The dtype to encode value_rowids if it doesn't already
have one. The default is tf.int64.
Returns:
A `RowPartition`.
Raises:
ValueError: If `nrows` is incompatible with `value_rowids`.
#### Example:
>>> print(RowPartition.from_value_rowids(
... value_rowids=[0, 0, 0, 0, 2, 2, 2, 3],
... nrows=4))
tf.RowPartition(row_splits=tf.Tensor([0 4 4 7 8], shape=(5,), dtype=int64))
"""
if not isinstance(validate, bool):
raise TypeError("validate must have type bool")
with ops.name_scope(None, "RowPartitionFromValueRowIds",
[value_rowids, nrows]):
value_rowids = cls._convert_row_partition(value_rowids, "value_rowids",
preferred_dtype)
if nrows is None:
const_rowids = tensor_util.constant_value(value_rowids)
if const_rowids is None:
nrows = array_ops.concat([value_rowids[-1:], [-1]], axis=0)[0] + 1
const_nrows = None
else:
const_nrows = const_rowids[-1] + 1 if const_rowids.size > 0 else 0
nrows = ops.convert_to_tensor(
const_nrows, value_rowids.dtype, name="nrows")
else:
nrows = ops.convert_to_tensor(nrows, value_rowids.dtype, "nrows")
const_nrows = tensor_util.constant_value(nrows)
if const_nrows is not None:
if const_nrows < 0:
raise ValueError("Expected nrows >= 0; got %d" % const_nrows)
const_rowids = tensor_util.constant_value(value_rowids)
if const_rowids is not None and const_rowids.size > 0:
if not const_nrows >= const_rowids[-1] + 1:
raise ValueError(
"Expected nrows >= value_rowids[-1] + 1; got nrows=%d, "
"value_rowids[-1]=%d" % (const_nrows, const_rowids[-1]))
value_rowids.shape.assert_has_rank(1)
nrows.shape.assert_has_rank(0)
if validate:
msg = ("Arguments to from_value_rowids do not form a valid "
"RowPartition")
checks = [
check_ops.assert_rank(value_rowids, 1, message=msg),
check_ops.assert_rank(nrows, 0, message=msg),
check_ops.assert_non_negative(value_rowids[:1], message=msg),
_assert_monotonic_increasing(value_rowids, message=msg),
check_ops.assert_less(value_rowids[-1:], nrows, message=msg),
]
value_rowids = control_flow_ops.with_dependencies(checks, value_rowids)
# Convert value_rowids & nrows to row_splits.
# Note: we don't use segment_ids_to_row_splits() here because we want
# to save the intermediate value `row_lengths`, so we can cache it.
# TODO(b/116708836) Upgrade bincount to accept int64 so we can skip the
# cast.
value_rowids_int32 = math_ops.cast(value_rowids, dtypes.int32)
nrows_int32 = math_ops.cast(nrows, dtypes.int32)
row_lengths = math_ops.bincount(
value_rowids_int32,
minlength=nrows_int32,
maxlength=nrows_int32,
dtype=value_rowids.dtype)
row_splits = array_ops.concat([[0], math_ops.cumsum(row_lengths)], axis=0)
if const_nrows is not None:
row_lengths.set_shape([const_nrows])
row_splits.set_shape([const_nrows + 1])
return cls(
row_splits=row_splits,
row_lengths=row_lengths,
value_rowids=value_rowids,
nrows=nrows,
internal=_row_partition_factory_key)
def __init__(self,
a=0.,
b=1.,
validate_args=False,
allow_nan_stats=True,
name="Uniform"):
"""Construct Uniform distributions with `a` and `b`.
The parameters `a` and `b` must be shaped in a way that supports
broadcasting (e.g. `b - a` is a valid operation).
Here are examples without broadcasting:
```python
# Without broadcasting
u1 = Uniform(3.0, 4.0) # a single uniform distribution [3, 4]
u2 = Uniform([1.0, 2.0], [3.0, 4.0]) # 2 distributions [1, 3], [2, 4]
u3 = Uniform([[1.0, 2.0],
[3.0, 4.0]],
[[1.5, 2.5],
[3.5, 4.5]]) # 4 distributions
```
And with broadcasting:
```python
u1 = Uniform(3.0, [5.0, 6.0, 7.0]) # 3 distributions
```
Args:
a: Floating point tensor, the minimum endpoint.
b: Floating point tensor, the maximum endpoint. Must be > `a`.
validate_args: `Boolean`, default `False`. Whether to validate input with
asserts. If `validate_args` is `False`, and the inputs are invalid,
correct behavior is not guaranteed.
allow_nan_stats: `Boolean`, default `True`. If `False`, raise an
exception if a statistic (e.g. mean/mode/etc...) is undefined for any
batch member. If `True`, batch members with valid parameters leading to
undefined statistics will return NaN for this statistic.
name: The name to prefix Ops created by this distribution class.
Raises:
InvalidArgumentError: if `a >= b` and `validate_args=False`.
"""
parameters = locals()
parameters.pop("self")
with ops.name_scope(name, values=[a, b]) as ns:
with ops.control_dependencies([
check_ops.assert_less(
a, b, message="uniform not defined when a > b.")
] if validate_args else []):
self._a = array_ops.identity(a, name="a")
self._b = array_ops.identity(b, name="b")
contrib_tensor_util.assert_same_float_dtype((self._a, self._b))
super(Uniform, self).__init__(dtype=self._a.dtype,
is_reparameterized=True,
is_continuous=True,
validate_args=validate_args,
allow_nan_stats=allow_nan_stats,
parameters=parameters,
graph_parents=[self._a, self._b],
name=ns)
def confusion_matrix(labels,
predictions,
num_classes=None,
weights=None,
dtype=dtypes.int32,
name=None):
"""Computes the confusion matrix from predictions and labels.
The matrix columns represent the prediction labels and the rows represent the
real labels. The confusion matrix is always a 2-D array of shape `[n, n]`,
where `n` is the number of valid labels for a given classification task. Both
prediction and labels must be 1-D arrays of the same shape in order for this
function to work.
If `num_classes` is `None`, then `num_classes` will be set to one plus the
maximum value in either predictions or labels. Class labels are expected to
start at 0. For example, if `num_classes` is 3, then the possible labels
would be `[0, 1, 2]`.
If `weights` is not `None`, then each prediction contributes its
corresponding weight to the total value of the confusion matrix cell.
For example:
```python
tf.math.confusion_matrix([1, 2, 4], [2, 2, 4]) ==>
[[0 0 0 0 0]
[0 0 1 0 0]
[0 0 1 0 0]
[0 0 0 0 0]
[0 0 0 0 1]]
```
Note that the possible labels are assumed to be `[0, 1, 2, 3, 4]`,
resulting in a 5x5 confusion matrix.
Args:
labels: 1-D `Tensor` of real labels for the classification task.
predictions: 1-D `Tensor` of predictions for a given classification.
num_classes: The possible number of labels the classification task can
have. If this value is not provided, it will be calculated
using both predictions and labels array.
weights: An optional `Tensor` whose shape matches `predictions`.
dtype: Data type of the confusion matrix.
name: Scope name.
Returns:
A `Tensor` of type `dtype` with shape `[n, n]` representing the confusion
matrix, where `n` is the number of possible labels in the classification
task.
Raises:
ValueError: If both predictions and labels are not 1-D vectors and have
mismatched shapes, or if `weights` is not `None` and its shape doesn't
match `predictions`.
"""
with ops.name_scope(name, 'confusion_matrix',
(predictions, labels, num_classes, weights)) as name:
labels, predictions = remove_squeezable_dimensions(
ops.convert_to_tensor(labels, name='labels'),
ops.convert_to_tensor(predictions, name='predictions'))
predictions = math_ops.cast(predictions, dtypes.int64)
labels = math_ops.cast(labels, dtypes.int64)
# Sanity checks - underflow or overflow can cause memory corruption.
labels = control_flow_ops.with_dependencies([
check_ops.assert_non_negative(
labels, message='`labels` contains negative values')
], labels)
predictions = control_flow_ops.with_dependencies([
check_ops.assert_non_negative(
predictions, message='`predictions` contains negative values')
], predictions)
if num_classes is None:
num_classes = math_ops.maximum(math_ops.reduce_max(predictions),
math_ops.reduce_max(labels)) + 1
else:
num_classes_int64 = math_ops.cast(num_classes, dtypes.int64)
labels = control_flow_ops.with_dependencies([
check_ops.assert_less(
labels, num_classes_int64, message='`labels` out of bound')
], labels)
predictions = control_flow_ops.with_dependencies([
check_ops.assert_less(predictions,
num_classes_int64,
message='`predictions` out of bound')
], predictions)
if weights is not None:
weights = ops.convert_to_tensor(weights, name='weights')
predictions.get_shape().assert_is_compatible_with(
weights.get_shape())
weights = math_ops.cast(weights, dtype)
shape = array_ops.stack([num_classes, num_classes])
indices = array_ops.stack([labels, predictions], axis=1)
values = (array_ops.ones_like(predictions, dtype)
if weights is None else weights)
return array_ops.scatter_nd(indices=indices,
updates=values,
shape=math_ops.cast(shape, dtypes.int64))
def __init__(self,
shift=None,
scale_identity_multiplier=None,
scale_diag=None,
scale_tril=None,
scale_perturb_factor=None,
scale_perturb_diag=None,
event_ndims=1,
validate_args=False,
name="affine"):
"""Instantiates the `Affine` bijector.
This `Bijector` is initialized with `shift` `Tensor` and `scale` arguments,
giving the forward operation:
```none
Y = g(X) = scale @ X + shift
```
where the `scale` term is logically equivalent to:
```python
scale = (
scale_identity_multiplier * tf.diag(tf.ones(d)) +
tf.diag(scale_diag) +
scale_tril +
scale_perturb_factor @ diag(scale_perturb_diag) @
tf.transpose([scale_perturb_factor])
)
```
If none of `scale_identity_multiplier`, `scale_diag`, or `scale_tril` are
specified then `scale += IdentityMatrix`. Otherwise specifying a
`scale` argument has the semantics of `scale += Expand(arg)`, i.e.,
`scale_diag != None` means `scale += tf.diag(scale_diag)`.
Args:
shift: Floating-point `Tensor`. If this is set to `None`, no shift is
applied.
scale_identity_multiplier: floating point rank 0 `Tensor` representing a
scaling done to the identity matrix.
When `scale_identity_multiplier = scale_diag = scale_tril = None` then
`scale += IdentityMatrix`. Otherwise no scaled-identity-matrix is added
to `scale`.
scale_diag: Floating-point `Tensor` representing the diagonal matrix.
`scale_diag` has shape [N1, N2, ... k], which represents a k x k
diagonal matrix.
When `None` no diagonal term is added to `scale`.
scale_tril: Floating-point `Tensor` representing the diagonal matrix.
`scale_diag` has shape [N1, N2, ... k, k], which represents a k x k
lower triangular matrix.
When `None` no `scale_tril` term is added to `scale`.
The upper triangular elements above the diagonal are ignored.
scale_perturb_factor: Floating-point `Tensor` representing factor matrix
with last two dimensions of shape `(k, r)`. When `None`, no rank-r
update is added to `scale`.
scale_perturb_diag: Floating-point `Tensor` representing the diagonal
matrix. `scale_perturb_diag` has shape [N1, N2, ... r], which
represents an `r x r` diagonal matrix. When `None` low rank updates will
take the form `scale_perturb_factor * scale_perturb_factor.T`.
event_ndims: Scalar `int32` `Tensor` indicating the number of dimensions
associated with a particular draw from the distribution. Must be 0 or 1.
validate_args: Python `bool` indicating whether arguments should be
checked for correctness.
name: Python `str` name given to ops managed by this object.
Raises:
ValueError: if `perturb_diag` is specified but not `perturb_factor`.
TypeError: if `shift` has different `dtype` from `scale` arguments.
"""
self._graph_parents = []
self._name = name
self._validate_args = validate_args
# Ambiguous definition of low rank update.
if scale_perturb_diag is not None and scale_perturb_factor is None:
raise ValueError("When scale_perturb_diag is specified, "
"scale_perturb_factor must be specified.")
# Special case, only handling a scaled identity matrix. We don't know its
# dimensions, so this is special cased.
# We don't check identity_multiplier, since below we set it to 1. if all
# other scale args are None.
self._is_only_identity_multiplier = (scale_tril is None
and scale_diag is None
and scale_perturb_factor is None)
# When no args are specified, pretend the scale matrix is the identity
# matrix.
if self._is_only_identity_multiplier and scale_identity_multiplier is None:
scale_identity_multiplier = 1.
with self._name_scope("init",
values=[
shift, scale_identity_multiplier, scale_diag,
scale_tril, scale_perturb_diag,
scale_perturb_factor, event_ndims
]):
event_ndims = ops.convert_to_tensor(event_ndims,
name="event_ndims")
if validate_args:
is_less_than_two = check_ops.assert_less(
event_ndims, 2, message="event_ndims must be 0 or 1")
event_ndims = control_flow_ops.with_dependencies(
[is_less_than_two], event_ndims)
self._shift = _as_tensor(shift, "shift")
# self._create_scale_operator returns an OperatorPD in all cases except if
# self._is_only_identity_multiplier; in which case it returns a scalar
# Tensor.
self._scale = self._create_scale_operator(
identity_multiplier=scale_identity_multiplier,
diag=scale_diag,
tril=scale_tril,
perturb_diag=scale_perturb_diag,
perturb_factor=scale_perturb_factor,
event_ndims=event_ndims,
validate_args=validate_args)
if (self._shift is not None and self._shift.dtype.base_dtype !=
self._scale.dtype.base_dtype):
raise TypeError(
"shift.dtype({}) does not match scale.dtype({})".format(
self._shift.dtype, self._scale.dtype))
self._shaper = _DistributionShape(
batch_ndims=self._infer_batch_ndims(),
event_ndims=event_ndims,
validate_args=validate_args)
super(Affine, self).__init__(
event_ndims=event_ndims,
graph_parents=(
[event_ndims] + [self._scale] if tensor_util.is_tensor(
self._scale) else self._scale.inputs +
[self._shift] if self._shift is not None else []),
is_constant_jacobian=True,
dtype=self._scale.dtype,
validate_args=validate_args,
name=name)