Method from_spec

tensorflow_datasets/core/splits.py:614–642

Creates a ReadInstruction instance out of a string spec. Args: spec (str): split(s) + optional slice(s) to read. A slice can be specified, using absolute numbers (int) or percentages (int). E.g. `test`: test split. `test + validation`: test split + validation split.

(cls, spec: SplitArg)

  @classmethod
  def from_spec(cls, spec: SplitArg) -> AbstractSplit:
    """Creates a ReadInstruction instance out of a string spec.

    Args:
      spec (str): split(s) + optional slice(s) to read. A slice can be
        specified, using absolute numbers (int) or percentages (int). E.g.
        `test`: test split. `test + validation`: test split + validation split.
        `test[10:]`: test split, minus its first 10 records. `test[:10%]`: first
        10% records of test split. `test[:-5%]+train[40%:60%]`: first 95% of
        test + middle 20% of train.

    Returns:
      The split instance.
    """
    if isinstance(spec, AbstractSplit):
      return spec

    spec = str(spec)  # Need to convert to str in case of `Split` instance.

    subs = _ADDITION_SEP_RE.split(spec)
    if not subs:
      raise ValueError(f'No instructions could be built out of {spec!r}')
    with utils.try_reraise(
        f'Error parsing split {spec!r}. See format at: '
        'https://www.tensorflow.org/datasets/splits\n'
    ):
      instructions = [_str_to_relative_instruction(s) for s in subs]
    # Merge all splits together (_SplitAll)
    return functools.reduce(operator.add, instructions)

  @abc.abstractmethod
  def to_absolute(self, split_infos) -> list[_AbsoluteInstruction]: