def _parameter_control_dependencies(self, is_init):
assertions = super(Wishart,
self)._parameter_control_dependencies(is_init)
if not self.validate_args:
assert not assertions
return []
if self._scale_full is None:
if is_init != tensor_util.is_ref(self._scale_tril):
shape = prefer_static.shape(self._scale_tril)
assertions.extend([
assert_util.assert_positive(
tf.linalg.diag_part(self._scale_tril),
message='`scale_tril` must be positive definite.'),
assert_util.assert_equal(
shape[-1],
shape[-2],
message='`scale_tril` must be square.')
])
else:
if is_init != tensor_util.is_ref(self._scale_full):
assertions.append(
distribution_util.assert_symmetric(self._scale_full))
return assertions
def __init__(self,
df,
scale,
cholesky_input_output_matrices=False,
validate_args=False,
allow_nan_stats=True,
name="WishartFull"):
"""Construct Wishart distributions.
Args:
df: `float` or `double` `Tensor`. Degrees of freedom, must be greater than
or equal to dimension of the scale matrix.
scale: `float` or `double` `Tensor`. The symmetric positive definite
scale matrix of the distribution.
cholesky_input_output_matrices: Python `bool`. Any function which whose
input or output is a matrix assumes the input is Cholesky and returns a
Cholesky factored matrix. Example `log_prob` input takes a Cholesky and
`sample_n` returns a Cholesky when
`cholesky_input_output_matrices=True`.
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.
"""
parameters = dict(locals())
with tf.name_scope(name) as name:
with tf.name_scope("init", values=[scale]):
scale = tf.convert_to_tensor(scale)
if validate_args:
scale = distribution_util.assert_symmetric(scale)
chol = tf.cholesky(scale)
chol = control_flow_ops.with_dependencies(
[tf.assert_positive(tf.matrix_diag_part(chol))]
if validate_args else [], chol)
super(WishartFull, self).__init__(
df=df,
scale_operator=tf.linalg.LinearOperatorLowerTriangular(
tril=chol,
is_non_singular=True,
is_positive_definite=True,
is_square=True),
cholesky_input_output_matrices=cholesky_input_output_matrices,
validate_args=validate_args,
allow_nan_stats=allow_nan_stats,
name=name)
self._parameters = parameters
def __init__(self,
df,
scale=None,
scale_tril=None,
input_output_cholesky=False,
validate_args=False,
allow_nan_stats=True,
name="Wishart"):
"""Construct Wishart distributions.
Args:
df: `float` or `double` `Tensor`. Degrees of freedom, must be greater than
or equal to dimension of the scale matrix.
scale: `float` or `double` `Tensor`. The symmetric positive definite
scale matrix of the distribution. Exactly one of `scale` and
'scale_tril` must be passed.
scale_tril: `float` or `double` `Tensor`. The Cholesky factorization
of the symmetric positive definite scale matrix of the distribution.
Exactly one of `scale` and 'scale_tril` must be passed.
input_output_cholesky: Python `bool`. If `True`, functions whose input or
output have the semantics of samples assume inputs are in Cholesky form
and return outputs in Cholesky form. In particular, if this flag is
`True`, input to `log_prob` is presumed of Cholesky form and output from
`sample`, `mean`, and `mode` are of Cholesky form. Setting this
argument to `True` is purely a computational optimization and does not
change the underlying distribution; for instance, `mean` returns the
Cholesky of the mean, not the mean of Cholesky factors. The `variance`
and `stddev` methods are unaffected by this flag.
Default value: `False` (i.e., input/output does not have Cholesky
semantics).
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:
ValueError: if zero or both of 'scale' and 'scale_tril' are passed in.
"""
parameters = dict(locals())
with tf.name_scope(name, values=[scale, scale_tril]) as name:
with tf.name_scope("init", values=[scale, scale_tril]):
if (scale is None) == (scale_tril is None):
raise ValueError(
"Must pass scale or scale_tril, but not both.")
if scale is not None:
scale = tf.convert_to_tensor(scale)
if validate_args:
scale = distribution_util.assert_symmetric(scale)
scale_tril = tf.cholesky(scale)
else: # scale_tril is not None
scale_tril = tf.convert_to_tensor(scale_tril)
if validate_args:
scale_tril = control_flow_ops.with_dependencies([
tf.assert_positive(
tf.matrix_diag_part(scale_tril),
message="scale_tril must be positive definite"
),
tf.assert_equal(
tf.shape(scale_tril)[-1],
tf.shape(scale_tril)[-2],
message="scale_tril must be square")
], scale_tril)
super(Wishart, self).__init__(
df=df,
scale_operator=tf.linalg.LinearOperatorLowerTriangular(
tril=scale_tril,
is_non_singular=True,
is_positive_definite=True,
is_square=True),
input_output_cholesky=input_output_cholesky,
validate_args=validate_args,
allow_nan_stats=allow_nan_stats,
name=name)
self._parameters = parameters
def __init__(self,
df,
scale=None,
scale_tril=None,
input_output_cholesky=False,
validate_args=False,
allow_nan_stats=True,
name="Wishart"):
"""Construct Wishart distributions.
Args:
df: `float` or `double` `Tensor`. Degrees of freedom, must be greater than
or equal to dimension of the scale matrix.
scale: `float` or `double` `Tensor`. The symmetric positive definite
scale matrix of the distribution. Exactly one of `scale` and
'scale_tril` must be passed.
scale_tril: `float` or `double` `Tensor`. The Cholesky factorization
of the symmetric positive definite scale matrix of the distribution.
Exactly one of `scale` and 'scale_tril` must be passed.
input_output_cholesky: Python `bool`. If `True`, functions whose input or
output have the semantics of samples assume inputs are in Cholesky form
and return outputs in Cholesky form. In particular, if this flag is
`True`, input to `log_prob` is presumed of Cholesky form and output from
`sample`, `mean`, and `mode` are of Cholesky form. Setting this
argument to `True` is purely a computational optimization and does not
change the underlying distribution; for instance, `mean` returns the
Cholesky of the mean, not the mean of Cholesky factors. The `variance`
and `stddev` methods are unaffected by this flag.
Default value: `False` (i.e., input/output does not have Cholesky
semantics).
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:
ValueError: if zero or both of 'scale' and 'scale_tril' are passed in.
"""
parameters = dict(locals())
with tf.name_scope(name, values=[scale, scale_tril]) as name:
with tf.name_scope("init", values=[scale, scale_tril]):
if (scale is None) == (scale_tril is None):
raise ValueError("Must pass scale or scale_tril, but not both.")
if scale is not None:
scale = tf.convert_to_tensor(scale)
if validate_args:
scale = distribution_util.assert_symmetric(scale)
scale_tril = tf.cholesky(scale)
else: # scale_tril is not None
scale_tril = tf.convert_to_tensor(scale_tril)
if validate_args:
scale_tril = control_flow_ops.with_dependencies([
tf.assert_positive(
tf.matrix_diag_part(scale_tril),
message="scale_tril must be positive definite"),
tf.assert_equal(
tf.shape(scale_tril)[-1],
tf.shape(scale_tril)[-2],
message="scale_tril must be square")
], scale_tril)
super(Wishart, self).__init__(
df=df,
scale_operator=tf.linalg.LinearOperatorLowerTriangular(
tril=scale_tril,
is_non_singular=True,
is_positive_definite=True,
is_square=True),
input_output_cholesky=input_output_cholesky,
validate_args=validate_args,
allow_nan_stats=allow_nan_stats,
name=name)
self._parameters = parameters
