tf.nest.assert_same_structure

Asserts that two structures are nested in the same way.

tf.nest.assert_same_structure(
    nest1, nest2, check_types=True, expand_composites=False
)

Refer to tf.nest for the definition of a structure.

Note the method does not check the types of atoms inside the structures.

Examples:

  • These atom vs. atom comparisons will pass:

    tf.nest.assert_same_structure(1.5, tf.Variable(1, tf.uint32))
tf.nest.assert_same_structure("abc", np.array([1, 2]))

  • These nested structure vs. nested structure comparisons will pass:

    structure1 = (((1, 2), 3), 4, (5, 6))
structure2 = ((("foo1", "foo2"), "foo3"), "foo4", ("foo5", "foo6"))
structure3 = [(("a", "b"), "c"), "d", ["e", "f"]]
tf.nest.assert_same_structure(structure1, structure2)
tf.nest.assert_same_structure(structure1, structure3, check_types=False)
  
    import collections
tf.nest.assert_same_structure(
    collections.namedtuple("bar", "a b")(1, 2),
    collections.namedtuple("foo", "a b")(2, 3),
    check_types=False)
  
    tf.nest.assert_same_structure(
    collections.namedtuple("bar", "a b")(1, 2),
    { "a": 1, "b": 2 },
    check_types=False)
  
    tf.nest.assert_same_structure(
    { "a": 1, "b": 2, "c": 3 },
    { "c": 6, "b": 5, "a": 4 })
  
    ragged_tensor1 = tf.RaggedTensor.from_row_splits(
      values=[3, 1, 4, 1, 5, 9, 2, 6],
      row_splits=[0, 4, 4, 7, 8, 8])
ragged_tensor2 = tf.RaggedTensor.from_row_splits(
      values=[3, 1, 4],
      row_splits=[0, 3])
tf.nest.assert_same_structure(
      ragged_tensor1,
      ragged_tensor2,
      expand_composites=True)

  • These examples will raise exceptions:

    tf.nest.assert_same_structure([0, 1], np.array([0, 1]))
  Traceback (most recent call last):

  ValueError: The two structures don't have the same nested structure
  
    tf.nest.assert_same_structure(
      collections.namedtuple('bar', 'a b')(1, 2),
      collections.namedtuple('foo', 'a b')(2, 3))
  Traceback (most recent call last):

  TypeError: The two structures don't have the same nested structure

nest1 an atom or a nested structure.
nest2 an atom or a nested structure.
check_types if True (default) types of structures are checked as well, including the keys of dictionaries. If set to False, for example a list and a tuple of objects will look the same if they have the same size. Note that namedtuples with identical name and fields are always considered to have the same shallow structure. Two types will also be considered the same if they are both list subtypes (which allows "list" and "_ListWrapper" from trackable dependency tracking to compare equal). check_types=True only checks type of sub-structures. The types of atoms are not checked.
expand_composites If true, then composite tensors such as tf.sparse.SparseTensor and tf.RaggedTensor are expanded into their component tensors.

ValueError If the two structures do not have the same number of atoms or if the two structures are not nested in the same way.
TypeError If the two structures differ in the type of sequence in any of their substructures. Only possible if check_types is True.