Python array_ops.constant方法代码示例

# 需要导入模块: from tensorflow.python.ops import array_ops [as 别名]
# 或者: from tensorflow.python.ops.array_ops import constant [as 别名]
def dense_to_sparse(tensor, eos_token=0, outputs_collections=None, scope=None):
  """Converts a dense tensor into a sparse tensor.

  An example use would be to convert dense labels to sparse ones
  so that they can be fed to the ctc_loss.

  Args:
     tensor: An `int` `Tensor` to be converted to a `Sparse`.
     eos_token: An integer. It is part of the target label that signifies the
       end of a sentence.
     outputs_collections: Collection to add the outputs.
     scope: Optional scope for name_scope.
  """
  with variable_scope.variable_scope(scope, 'dense_to_sparse', [tensor]) as sc:
    tensor = ops.convert_to_tensor(tensor)
    indices = array_ops.where(
        math_ops.not_equal(tensor, constant_op.constant(eos_token,
                                                        tensor.dtype)))
    values = array_ops.gather_nd(tensor, indices)
    shape = array_ops.shape(tensor, out_type=dtypes.int64)
    outputs = sparse_tensor.SparseTensor(indices, values, shape)
    return utils.collect_named_outputs(outputs_collections, sc.name, outputs) 

# 需要导入模块: from tensorflow.python.ops import array_ops [as 别名]
# 或者: from tensorflow.python.ops.array_ops import constant [as 别名]
def _safe_scalar_div(numerator, denominator, name):
  """Divides two values, returning 0 if the denominator is 0.

  Args:
    numerator: A scalar `float64` `Tensor`.
    denominator: A scalar `float64` `Tensor`.
    name: Name for the returned op.

  Returns:
    0 if `denominator` == 0, else `numerator` / `denominator`
  """
  numerator.get_shape().with_rank_at_most(1)
  denominator.get_shape().with_rank_at_most(1)
  return control_flow_ops.cond(
      math_ops.equal(
          array_ops.constant(0.0, dtype=dtypes.float64), denominator),
      lambda: array_ops.constant(0.0, dtype=dtypes.float64),
      lambda: math_ops.div(numerator, denominator),
      name=name) 

# 需要导入模块: from tensorflow.python.ops import array_ops [as 别名]
# 或者: from tensorflow.python.ops.array_ops import constant [as 别名]
def __init__(
      self, dtypes, shapes=None, capacity=10, shared_name='feeding_queue'):
    self._dtypes = dtypes
    self._shapes = shapes
    self._shared_name = shared_name
    self._capacity = capacity
    self._local_q = data_flow_ops.FIFOQueue(capacity=self._capacity,
                                            dtypes=self._dtypes,
                                            shapes=self._shapes,
                                            name=self._shared_name,
                                            shared_name=self._shared_name)
    self._num_remote_feeds = 0

    # Fake do-nothing operation that's used to prevent remote queues
    # from being closed, and as a workaround for b/32749157
    self._fake_op = array_ops.constant('dummy close', name='feeder_fake_op').op
    self._feeding_event = threading.Event() 

# 需要导入模块: from tensorflow.python.ops import array_ops [as 别名]
# 或者: from tensorflow.python.ops.array_ops import constant [as 别名]
def testOverflow(self):
    x = [1000, 1001, 1002, 1003]
    for dtype in [np.float16, np.float32, np.double]:
      x_np = np.array(x, dtype=dtype)
      max_np = np.max(x_np)
      with self.assertRaisesRegexp(RuntimeWarning,
                                   "overflow encountered in exp"):
        out = log(np.sum(exp(x_np)))
        if out == np.inf:
          raise RuntimeWarning("overflow encountered in exp")

      with self.test_session(use_gpu=True):
        x_tf = constant_op.constant(x_np, shape=x_np.shape)
        y_tf_np = math_ops.reduce_logsumexp(x_tf).eval()
        y_np = log(np.sum(exp(x_np - max_np))) + max_np
        self.assertAllClose(y_tf_np, y_np) 

# 需要导入模块: from tensorflow.python.ops import array_ops [as 别名]
# 或者: from tensorflow.python.ops.array_ops import constant [as 别名]
def testUnderflow(self):
    x = [-1000, -1001, -1002, -1003]
    for dtype in [np.float16, np.float32, np.double]:
      x_np = np.array(x, dtype=dtype)
      max_np = np.max(x_np)
      with self.assertRaisesRegexp(RuntimeWarning,
                                   "divide by zero encountered in log"):
        out = log(np.sum(exp(x_np)))
        if out == -np.inf:
          raise RuntimeWarning("divide by zero encountered in log")

      with self.test_session(use_gpu=True):
        x_tf = constant_op.constant(x_np, shape=x_np.shape)
        y_tf_np = math_ops.reduce_logsumexp(x_tf).eval()
        y_np = log(np.sum(exp(x_np - max_np))) + max_np
        self.assertAllClose(y_tf_np, y_np) 

# 需要导入模块: from tensorflow.python.ops import array_ops [as 别名]
# 或者: from tensorflow.python.ops.array_ops import constant [as 别名]
def testConsistent(self):
    nums, divs = self.intTestData()
    with self.test_session():
      tf_result = (
          math_ops.floor_div(nums, divs) * divs + math_ops.floor_mod(nums, divs)
      ).eval()
      tf_nums = array_ops.constant(nums)
      tf_divs = array_ops.constant(divs)
      tf2_result = (tf_nums // tf_divs * tf_divs + tf_nums % tf_divs).eval()
      np_result = (nums // divs) * divs + (nums % divs)
      # consistentcy with numpy
      self.assertAllEqual(tf_result, np_result)
      # consistentcy with two forms of divide
      self.assertAllEqual(tf_result, tf2_result)
      # consistency for truncation form
      tf3_result = (
          math_ops.truncatediv(nums, divs) * divs
          + math_ops.truncatemod(nums, divs)
      ).eval()
      expanded_nums = np.reshape(np.tile(nums, divs.shape[1]),
                                 (nums.shape[0], divs.shape[1]))
      # Consistent with desire to get numerator
      self.assertAllEqual(tf3_result, expanded_nums)
      # Consistent with desire to get numerator
      self.assertAllEqual(tf_result, expanded_nums) 

# 需要导入模块: from tensorflow.python.ops import array_ops [as 别名]
# 或者: from tensorflow.python.ops.array_ops import constant [as 别名]
def report_uninitialized_resources(resource_list=None,
                                   name="report_uninitialized_resources"):
  """Returns the names of all uninitialized resources in resource_list.

  If the returned tensor is empty then all resources have been initialized.

  Args:
   resource_list: resources to check. If None, will use shared_resources() +
    local_resources().
   name: name for the resource-checking op.

  Returns:
   Tensor containing names of the handles of all resources which have not
   yet been initialized.

  """
  if resource_list is None:
    resource_list = shared_resources() + local_resources()
  with ops.name_scope(name):
    if not resource_list:
      # Return an empty tensor so we only need to check for returned tensor
      # size being 0 as an indication of model ready.
      return array_ops.constant([], dtype=dtypes.string)
    # Get a 1-D boolean tensor listing whether each resource is initialized.
    variables_mask = math_ops.logical_not(
        array_ops.stack([r.is_initialized for r in resource_list]))
    # Get a 1-D string tensor containing all the resource names.
    variable_names_tensor = array_ops.constant(
        [s.handle.name for s in resource_list])
    # Return a 1-D tensor containing all the names of uninitialized resources.
    return array_ops.boolean_mask(variable_names_tensor, variables_mask) 

# 需要导入模块: from tensorflow.python.ops import array_ops [as 别名]
# 或者: from tensorflow.python.ops.array_ops import constant [as 别名]
def report_uninitialized_variables(var_list=None,
                                   name="report_uninitialized_variables"):
  """Adds ops to list the names of uninitialized variables.

  When run, it returns a 1-D tensor containing the names of uninitialized
  variables if there are any, or an empty array if there are none.

  Args:
    var_list: List of `Variable` objects to check. Defaults to the
      value of `global_variables() + local_variables()`
    name: Optional name of the `Operation`.

  Returns:
    A 1-D tensor containing names of the uninitialized variables, or an empty
    1-D tensor if there are no variables or no uninitialized variables.
  """
  if var_list is None:
    var_list = global_variables() + local_variables()
    # Backwards compatibility for old-style variables. TODO(touts): remove.
    if not var_list:
      var_list = []
      for op in ops.get_default_graph().get_operations():
        if op.type in ["Variable", "VariableV2", "AutoReloadVariable"]:
          var_list.append(op.outputs[0])
  with ops.name_scope(name):
    if not var_list:
      # Return an empty tensor so we only need to check for returned tensor
      # size being 0 as an indication of model ready.
      return array_ops.constant([], dtype=dtypes.string)
    else:
      # Get a 1-D boolean tensor listing whether each variable is initialized.
      variables_mask = math_ops.logical_not(
          array_ops.stack(
              [state_ops.is_variable_initialized(v) for v in var_list]))
      # Get a 1-D string tensor containing all the variable names.
      variable_names_tensor = array_ops.constant([s.op.name for s in var_list])
      # Return a 1-D tensor containing all the names of uninitialized variables.
      return array_ops.boolean_mask(variable_names_tensor, variables_mask)

# pylint: disable=protected-access 

# 需要导入模块: from tensorflow.python.ops import array_ops [as 别名]
# 或者: from tensorflow.python.ops.array_ops import constant [as 别名]
def PostProcessing(self):
    """Perform postprocessing at the end of gradients().

    We have created the gradient graph at this point. So this function
    can be used to perform any postprocessing on the gradient graph.
    We currently perform the following postprocessing:
      1. Patch the gradient graph if the output of a loop variable
         doesn't depend on its input.
    """
    for _, grad_state in self._map.items():
      for _, b_merge in grad_state.switch_map.items():
        if b_merge.op.inputs[0] == b_merge.op.inputs[1]:
          # The value of this loop variable at iteration i+1 doesn't
          # depend on its value at iteration i. So use zeros as the
          # gradients for all iterations > 0.
          dtype = b_merge.op.inputs[0].dtype
          shape = b_merge.op.inputs[0].get_shape()
          # pylint: disable=protected-access
          if shape.is_fully_defined():
            grad_state.grad_context.Enter()
            # Create a zeros and use it for iterations > 0.
            grad_val = constant_op.constant(0, dtype=dtype, shape=shape)
            next_grad_val = _NextIteration(grad_val)
            grad_state.grad_context.Exit()
          else:
            # Create a zeros in the outer grad context.
            outer_grad_ctxt = grad_state.grad_context.outer_context
            if outer_grad_ctxt: outer_grad_ctxt.Enter()
            enter_grad_op = b_merge.op.inputs[0].op
            enter_grad = enter_grad_op.inputs[0]
            grad_shape = array_ops.shape_internal(enter_grad, optimize=False)
            grad_val = array_ops.zeros(grad_shape)
            if outer_grad_ctxt: outer_grad_ctxt.Exit()
            # Use the zeros for iterations > 0.
            grad_state.grad_context.Enter()
            next_grad_val = _NextIteration(grad_val)
            grad_state.grad_context.Exit()
          b_merge.op._update_input(1, next_grad_val)
          # pylint: enable=protected-access 

# 需要导入模块: from tensorflow.python.ops import array_ops [as 别名]
# 或者: from tensorflow.python.ops.array_ops import constant [as 别名]
def _event_shape_tensor(self):
    return array_ops.constant([], dtype=dtypes.int32) 

# 需要导入模块: from tensorflow.python.ops import array_ops [as 别名]
# 或者: from tensorflow.python.ops.array_ops import constant [as 别名]
def _SegmentMeanGrad(op, grad):
  """Gradient for SegmentMean."""
  input_rank = array_ops.rank(op.inputs[0])
  ones_shape = array_ops.concat([
      array_ops.shape(op.inputs[1]),
      array_ops.fill(array_ops.expand_dims(input_rank - 1, 0), 1)
  ], 0)
  ones = array_ops.fill(ones_shape,
                        constant_op.constant(1, dtype=grad.dtype))
  scaled_grad = math_ops.div(grad, math_ops.segment_sum(ones, op.inputs[1]))
  return array_ops.gather(scaled_grad, op.inputs[1]), None 

# 需要导入模块: from tensorflow.python.ops import array_ops [as 别名]
# 或者: from tensorflow.python.ops.array_ops import constant [as 别名]
def _ErfcGrad(op, grad):
  """Returns -grad * 2/sqrt(pi) * exp(-x**2)."""
  x = op.inputs[0]
  minus_two_over_root_pi = constant_op.constant(
      -2 / np.sqrt(np.pi), dtype=grad.dtype)
  with ops.control_dependencies([grad.op]):
    x = math_ops.conj(x)
    return grad * minus_two_over_root_pi * math_ops.exp(-math_ops.square(x)) 

# 需要导入模块: from tensorflow.python.ops import array_ops [as 别名]
# 或者: from tensorflow.python.ops.array_ops import constant [as 别名]
def _DigammaGrad(op, grad):
  """Compute gradient of the digamma function with respect to its argument."""
  x = op.inputs[0]
  with ops.control_dependencies([grad.op]):
    x = math_ops.conj(x)
    return grad * math_ops.polygamma(array_ops.constant(1, dtype=x.dtype), x) 

# 需要导入模块: from tensorflow.python.ops import array_ops [as 别名]
# 或者: from tensorflow.python.ops.array_ops import constant [as 别名]
def _AsinGrad(op, grad):
  """Returns grad * 1/sqrt(1-x^2)."""
  x = op.inputs[0]
  with ops.control_dependencies([grad.op]):
    x = math_ops.conj(x)
    x2 = math_ops.square(x)
    one = constant_op.constant(1, dtype=grad.dtype)
    den = math_ops.sqrt(math_ops.subtract(one, x2))
    inv = math_ops.reciprocal(den)
    return grad * inv 

# 需要导入模块: from tensorflow.python.ops import array_ops [as 别名]
# 或者: from tensorflow.python.ops.array_ops import constant [as 别名]
def _AcosGrad(op, grad):
  """Returns grad * -1/sqrt(1-x^2)."""
  x = op.inputs[0]
  with ops.control_dependencies([grad.op]):
    x = math_ops.conj(x)
    x2 = math_ops.square(x)
    one = constant_op.constant(1, dtype=grad.dtype)
    den = math_ops.sqrt(math_ops.subtract(one, x2))
    inv = math_ops.reciprocal(den)
    return -grad * inv