def get_all_positions(dataset, num_workers=<NUM_LIT:1>):
positions = []<EOL>identifiers = tqdm(<EOL>list(get_all_identifiers(dataset)), desc="<STR_LIT>" % dataset.name)<EOL>with Pool(num_workers) as pool:<EOL><INDENT>for directory, identifier, position in pool.map(_get_position_worker, identifiers):<EOL><INDENT>positions.append((directory, identifier, position))<EOL><DEDENT><DEDENT>for directory, identifier, position in positions:<EOL><INDENT>yield (directory, identifier, position)<EOL><DEDENT>
Extracts paragraph identifiers, and positions from a dataset in the NTCIR-11 Math-2, and
NTCIR-12 MathIR XHTML5 format.

Parameters
----------
dataset : Path
    A path to a dataset.
num_workers : int, optional
    The number of processes that will extract paragraph positions from the dataset.

Yields
-------
(Path, str, float)
    A parent directory of a paragraph, the identifier of the paragraph, and an estimate of the
    position of the paragraph in its parent document. The position is in the range [0; 1).